Below: The Doctor becomes Peter Capaldi.
Often in cases of ensemble series, a character introduced into the series sometime later will be played by an actor who appeared on the show much earlier in a guest appearance as an entirely different character. In some cases, it could be because the cast and crew enjoyed working with the actor enough to create a new regular or recurring character to be able to work with him more regularly, but a lot of the time, there's no actual explanation behind it.
The use of the same actor for different characters is typically intended to go unnoticed or at least unremarked. For example, Ed Wasser played Shadow minion Morden in Babylon 5 but also appeared in the series pilot as a minor crew member named in the credits as Guerra. Since that series was so intricately plotted, fans wondered if the Shadows were influencing events as far back as the pilot. No, said series creator J. Michael Straczynski, they just liked the actor's work in the pilot and cast him in a recurring role.
Spin-off shows will often encounter this, as the producers find actors they like for the new show.
Occasionally, if a series or franchise runs long enough, the inversion may also occur: an actor who played a regular role leaves, then returns guest-starring as a different character.
Subtrope of You Look Familiar. Compare Ascended Extra and Early-Bird Cameo.
Examples:
- Houko Kuwashima played the Arrancar Cirucci Sanderwicci in Bleach before she took over for the ailing Tomoko Kawakami note as Soifon. She also took over for Kawakami as Fuyuki Hinata in Sgt. Frog after playing Meru in the 2007 Sgt. Frog movie The Deep Sea Princess.
- Detective Conan:
- Ryo Horikawa played the Victim of the Week in the 6th episode before later playing Shinichi's fellow detective Heiji Hattori.
- Rikiya Koyama had several minor roles throughout the franchise, including Tadaki Kai in The Mirapolis Investigation video game, before he succeeded Akira Kamiya as Kogoro Mori.
- Several from Digimon
- Enzo Fortuny voiced Frigimon and Pumpkinmon in the Mexican Spanish dub of Digimon Adventure before replacing Gerry Mesa as Tai during Digimon Adventure 02.
- Tamara Guzman voiced Tai's mom and Terriermon from Digimon: The Movie before voicing Kari and Gatomon in 02.
- On the Japanese side, Reiko Kiuchi voiced a Koromon in episode 12 of Adventure before she was cast as Daisuke/Davis in 02.
- Tomokazu Seki had several roles in a few Doraemon movies, most prominently young Suneo in 2000's A Grandmother's Recollections. Seki took up the role of Suneo full-time when the voice cast changed in 2005.
- Masako Nozawa voiced Botako, a minor character with seven episodes to her credit, in the 1973 Doraemon anime, before she took over for Kousei Tomita as the title character in the second half.
- Dragon Ball:
- Takeshi Aono voiced Ninja Murasaki in the Red Ribbon Army arc and later returned as King Piccolo and Kami.
- Toshio Furukawa played minor villain General Blue during the Red Ribbon Army arc. He later returned to the franchise two years later as Goku's enemy turned eventual ally Piccolo.
- Ryo Horikawa appears in one episode reprising his role as Charmy from Doctor Slump. He showed up again one series later in Dragon Ball Z as franchise mainstay Vegeta.
- Masaharu Sato voiced many one-episode characters throughout the original Dragon Ball series, including the Bear Thief in Episode 3 and a Rabbit Gang member in Episode 12, before he was cast as Staff Officer Black. He also voiced Master Roshi in Wrath of the Dragon following Kouhei Miyauchi's death, but he wouldn't take over for Roshi fulltime until Kai.
- Ryusei Nakao played Tamborine in the King Piccolo arc and returned a few years later to play the even-more iconic Big Bad Freeza.
- Takeshi Kusao is in an early filler episode of Dragon Ball Z as Pigero, a one-shot character who helps out Gohan. He returns over a hundred episodes later as Breakout Character Trunks. Aya Hisakawa played Chiko in the same episode, then returned nearly thirty years later to assume the role of Bulma after the death of her longtime actress, Hiromi Tsuru.
- Kōzō Shioya provided the voice of Guldo from the Ginyu Force during the Freeza Saga in Dragon Ball Z. He would return over 100 episodes later to portray the anime's final major antagonist, Majin Buu.
- Kōichi Yamadera portrayed Tenshinhan for a few episodes in Dragon Ball Z when Hirotaka Suzuoki was unavailable. He returned to the franchise over two decades later to play Beerus in the films Battle of Gods and Resurrection 'F' and the TV series Dragon Ball Super.
- Masakazu Morita played Vegeta's younger brother Tarble in the OVA Dragon Ball: Yo! Son Goku and His Friends Return!! and returned a few years later to voice Whis beginning with Battle of Gods.
- For the English dub, Monica Rial had a minor role as Coco in the film Dragon Ball Z: Broly Second Coming. Five years later she would take over as the new voice actress for Bulma after Tiffany Volmer's retirement beginning with Dragon Ball Z Kai.
- Also for the English dub, Colleen Clinkenbeard provided the voice of Zangya in Dragon Ball Z: Bojack Unbound, before later taking over more substantial roles in the franchise as Mai beginning with the third game in the Dragon Ball Z: Budokai Tenkaichi series, Kid Gohan beginning with Dragon Ball Z Kai, and Kid Goku beginning with Curse of the Blood Rubies.
- Kyle Hebert played several minor characters, in addition to a minor recurring role as the Ox-King, before being cast as the voice of the older Gohan and The Narrator starting in the Majin Buu Saga.
- In Fist of the North Star, Kaneto Shiozawa voiced a side character of the week named Dr. Duran several episodes before the debut of his iconic role as Rei.
- Fullmetal Alchemist:
- Unshou Ishizuka played Huskisson, a Starter Villain in the film Conqueror of Shamballa that continued from the 2003 anime. When Fullmetal Alchemist Brotherhood, the anime that followed the original manga story closer, was made four years later, he portrayed Ed and Al's father, Hohenheim.
- Nana Mizuki first portrayed Armony in the PS2 video game Fullmetal Alchemist and the Broken Angel before getting cast in the 2003 anime as Wrath and in Brotherhood as Lanfan.
- Fumiko Orikasa voiced one-shot character Lydia in episode 35 of the 2003 anime, then voiced Riza Hawkeye in Brotherhood.
- In the English dub of the 2003 series, Kent Williams played Majihal, a one-shot villain in the fourth episode. When Brotherhood was dubbed in English he played the main villain, Father.
- Gundam:
- Keiko Han appeared early on in Mobile Suit Gundam as the doomed Icelina Eschonbach, and returned in the final stretch as the doomed Lalah Sune.
- Kazuki Yao had several minor roles in Mobile Suit Zeta Gundam, including Sorama and Gates Capa, before getting cast as Judau Ashta in Mobile Suit Gundam ZZ.
- In JoJo's Bizarre Adventure, Junichi Suwabe voiced minor antagonist D'Arby Younger from JoJo's Bizarre Adventure: Stardust Crusaders was later cast as Leone Abbacchio in JoJo's Bizarre Adventure: Vento Aureo.
- Kōichi Yamadera had some guest spots on a few Lupin III movies, such as Michael Suzuki in Crisis in Tokyo, before succeeding Gorō Naya as Inspector Zenigata in 2011.
- One Piece:
- Kazuki Yao played minor recurring villains Django and Mr. 2 Bon Clay before playing Franky, one of the members of the Straw Hat crew.
- The same goes for fellow Straw Hat Brook, whose voice actor, Cho, previously played minor characters Barbarossa and Henzo.
- Kazue Ikura stood-in for Ikue Otani as Tony Tony Chopper when the latter went on maternity leave, and later returned as Sentomaru.
- Toru Furuya played filler character Daddy Masterson in Episode 50, then returned a few hundred or so episodes later as the adult Sabo.
- Aoi Yūki voiced minor recurring character Aika Nakamura in Persona 4: The Animation before voicing main party member Futaba Sakura in Persona 5. Ditto for Aika's English voice actor Cassandra Lee Morris, who would later on voice main party member Morgana.
- Although the All Stars-recognized Pretty Cures tend to have one completely different voice actress each, some of them had voiced minor characters before voicing Precures.
- Junko Takeuchi voiced Kenta Hoshino before voicing Cure Rouge.note
- Mariya Ise voiced Mari Yamaguchi before voicing Cure Lemonade.
- Ai Nagano voiced Yoshimi Takenouchi and Seekun before voicing Cure Mint (and also her identical Cool Big Sis).
- Eri Sendai voiced Shiho Kubota and Harmonin before voicing Milky Rose.
- Kanae Oki voiced several students and Aki Yamamoto before voicing Cure Peach.
- Akiko Nakagawa voiced Chiaki Yabe, Kaya Andou, and a woman before voicing Cure Pine.
- Fumie Mizusawa voiced Miu Kagamiya and Eternalun before voicing Cure Marine.
- Ami Koshimizu voiced the wannabe Cure, Natsuko Koshino before voicing Cure Melody.
- Fumiko Orikasa voiced Katsuko Nagasawa and Azusa Takagishi before voicing Cure Rhythm.
- Misato Fukuen voiced a boy named Tomoya before voicing Cure Happy.
- Chinami Nishimura voiced Dark Dream before voicing Cure Beauty.note
- Hitomi Nabatame voiced Yumiko Nakagawa before voicing Cure Heart.
- Mai Fuchigami voiced a student council executive in HeartCatch Pretty Cure! before voicing Cure Rosetta.
- Kanako Miyamoto voiced "herself" in Yes! Pretty Cure 5 before voicing Cure Sword. She also returned cameoing in Kirakira★PreCure a la Mode as an idol named Kanako.note
- Rie Kugimiya voiced Dark Lemonade before voicing Cure Ace.note
- Megumi Han voiced a child in Smile Pretty Cure! before voicing Cure Princess.
- Yu Shimamura voiced a girl in Suite Pretty Cure ♪ before voicing Cure Flora.
- Miyuki Sawashiro voiced some girl named Arisa before voicing Cure Scarlet.
- Rie Takahashi voiced a student in Go! Princess Pretty Cure before voicing Cure Miracle.
- Yui Horie voiced Tsumugi Orihara before voicing Cure Magical.
- Tomo Muranaka voiced Kin before voicing Cure Gelato.
- Saki Fujita voiced the Past Cure Flora, Chieri before voicing Cure Macaron.
- Rie Hikisaka voiced Junko Mitsuoka before voicing Cure Yell.
- Kiyono Yasuno voiced Cure Lumière before voicing Cure Soleil.note
- Aoi Yūki voiced Cook before voicing Cure Grace.
- Natsu Yorita voiced the Gemini Star Princess, Takuto and Ikuto Amamiya before voicing Cure Fontaine.
- In the 1997 Record of Lodoss War anime, Junko Noda voiced a character named Arteen in the first episode. She later took over as Deedlit in the last six episodes when Shiho Niiyama took ill.
- Sailor Moon:
- Emi Shinohara voiced Youmas Cyrene and Jumeau before she took on the role of Makoto Kino/Sailor Jupiter.
- Kae Araki stood in for Kotono Mitsuishi as Sailor Moon for the last few episodes of season one, and the first few of R when Mitsuishi went on medical leave. She returned shortly after that stint as Chibi-Usa.
- Daisuke Sakaguchi had a few minor roles in season one and S before he was cast in SuperS as newly-promoted supporting character Kyuusuke Sarashima, who was previously voiced by Kazumi Okushima in his sole appearance in R.
- Two of the Sailor Starlights of Sailor Stars previously had guest spots in SuperS. Shiho Niiyama (Seiya/Sailor Star Fighter) was Fuyumi in Episode 139, while Chika Sakamoto (Yaten/Sailor Star Maker) was Perle in The Movie.
- Yu Yu Hakusho:
- Megumi Ogata made her debut as a voice actress voicing several minor characters, including the mother of the boy Yusuke saved and Keiko's mother, before her main role Kurama finally debuted.
- Meanwhile, Nobuyuki Hiyama had a few minor roles in Episode 1, namely the student Yusuke confronts at school and the reckless driver who kills Yusuke, before his main role Hiei finally debuted.
- Norio Wakamoto voiced Gouki, the third member of Kurama and Hiei's trio before he came back as Yusuke's Dark Tournament foe turned ally, Chu.
- Kazuyuki Sogabe voiced Gama, Kurama's Dark Tournament opponent, before he voiced another Tournament opponent turned ally, Suzuki. Similarly, Toshiyuki Morikawa (Shishiwakamaru) voiced several minor roles, including Roto.
- DC Extended Universe:
- Samantha Jo played one-shot minor villain Car-Vex in Man of Steel. She went on to play the Amazon Euboea in both Wonder Woman and Justice League, who has a tad more notable things to do.
- Patrick Wilson voiced the U.S. President in Batman v Superman: Dawn of Justice, then played Orm in Aquaman, who's also set to reappear in the Aquaman sequel.
- In Ernest Goes to Camp, Gailard Sartain plays Jake, one of the bumbling cooks at Kamp Kikakee. In subsequent Ernest movies (as well as the Hey Vern, it's Ernest! TV series, and a series of commercials produced by Carden-Cherry - the same advertising firm that created the original Ernest commercials) he plays Chuck, Ernest's loud-mouthed and Know-Nothing Know-It-All pal and neighbor, and "twin brother" of Bobby.
- Joe Don Baker played James Bond's CIA contact in both GoldenEye and Tomorrow Never Dies, after having played a villain in The Living Daylights.
- Marvel Cinematic Universe:
- Enver Gjokaj had a cameo in The Avengers as a NYPD cop. He was later cast as Daniel Sousa in the prequel series Agent Carter, with the producers joking that the cop is Sousa's Identical Grandson.
- Alfre Woodard cameoed in Captain America: Civil War as a mother to one of the casualties of Avengers: Age of Ultron. She was later cast as major antagonist Mariah Dillard in Luke Cage (2016).
- Laura Haddock played a woman asking Steve for an autograph in Captain America: The First Avenger before playing Meredith Quill in the Guardians of the Galaxy films. Similar to the Gjokaj example above, James Gunn joked that the woman was Peter Quill's grandmother.
- Peter Mensah had a minor role in The Incredible Hulk as a colleague of General Ross before playing Recurring Character Qovas in Agents of S.H.I.E.L.D..
- The Adventures of Robin Hood reused actors all the time. The most frequent was Paul Eddington, who played dozens of different roles over the show's five-year run - and combined this trope with The Other Darrin in 1959 when Will Scarlet (hitherto an occasional guest character played by Ron Howard) was promoted to a regular character played by Eddington.
- In the All in the Family episode "Lionel Moves Into the Neighborhood", Vincent Gardenia plays Archie's neighbor who sells his house to the Jeffersons. In "The Bunkers and the Swingers", a swinger couple is played by Gardenia and Rue McClanahan. Gardenia would appear in the recurring role of Frank Lorenzo from the next season. McClanahan would later appear as Maude's friend, Vivian in the spinoff Maude.
- Alphas/Eureka/Warehouse 13: (Due to the crossover of Lindsay Wagner's Dr. Vanessa Calder from Warehouse 13 onto an episode of Alphas, and the multiple crossover episodes between Eureka and Warehouse 13, all three can be considered in a Shared Universe.)
- Laura Mennell originally appeared on Eureka as Dr. Rivers and was later recast as Alphas main cast member Nina Theroux.
- Saul Rubinek was originally Dr. Carl Carlson on Eureka before becoming Artie Nielsen on Warehouse 13.
- Jane Moffat appeared on a Warehouse 13 episode as Wanda before being in eight episodes of Alphas as Sandra Bell.
- The Andy Griffith Show:
- In the Poorly Disguised Pilot that appeared on Make Room For Daddy, Frances Bavier, who played Aunt Bee in the regular series, portrayed Mayberry citizen Henrietta Perkins in the pilot episode.
- Jack Dodson appeared in one Season 6 episode as an insurance agent before taking on the role of county clerk Howard Sprague the following season.
- Howard Morris is an aversion of this: he was already the mischevious, rock-throwing and window-breaking mountain nut Ernest T. Bass, however in one episode, he randomly appeared as a mild-mannered, and soft-spoken TV repairman.
- On A.N.T. Farm, Winter Maddox, the ANTs "Den Mother" in Season 3 was Madam Goo Goo, a one-shot character in Season 1 who was a Lady Gaga clone.
- Patrick Newell had brief roles in The Avengers (1960s) episodes "The Town of No Return" and "Something Nasty in the Nursery" before playing Mother in the show's final season.
- Babylon 5:
- Ed Wasser appeared in the pilot movie as a crewman on the Babylon 5 command deck, before being cast in a regular role as Shadow minion Morden.
- Robin Atkin Downes played a Minbari in In The Beginning and had a regular role as the rebel telepath Byron in season five.
- Barney Miller:
- Steve Landesberg appeared in one first-season episode as a priest before being cast as the know-it-all detective Arthur Dietrich in the second season.
- Ron Carey played a cat burglar called "The Mole" who led the detectives in a chase down the sewers. He was later cast as a uniformed cop named Levitt, who was a regular for the rest of the show's run.
- Paul Lieber played a gang member who tries to break his buddy out of jail in one 6th season episode; in season 7 Lieber plays new Detective Dorsey, who ruffles the rest of the squad by assuming they're all on the take. However, when they decided that season 7 would be the last season his character was dropped.
- Bewitched:
- Before becoming Uncle Arthur in Season Two, Paul Lynde appeared in the Season One episode "Driving is the Only Way to Fly" as Harold Harold, the insecure and neurotic instructor who was hired to teach Samantha how to drive. Elizabeth Montgomery and Paul Lynde loved working together so much and the crew got such a big kick out of him that Uncle Arthur was created so they could work with him on a semi-regular basis.
- Before playing witch doctor Dr. Bombay in Season Three, Bernard Fox appeared as a witch hunter in Season Two's "Disappearing Samantha" in which his incantation for making witches disappear affects Samantha, leaving Darrin and Endora to look for a way to get information from him on how to reverse it.
- The first appearance of Alice Ghostly was as maid Naomi Hogan before she appeared regularly as Esmeralda.
- Hugh Laurie appeared as different characters in two episodes of Blackadder II, first as Simon Partridge and then as Prince Ludwig the Indestructible. He then played regular roles in the show's third and fourth series, in Blackadder the Third as George, Prince of Wales, and in Blackadder Goes Forth as Lieutenant George Colthurst St Barleigh.
- In Blake's 7, Glynis Barber played the regular character Soolin in the final season, after playing a tiny role in one episode of the first season as one of the Federation's techno-undead "Mutoid" soldiers.
- Rebecca Breeds plays Cassie Cometti in season 3 of Blue Water High, but she made her first appearance in season 2, episode 3 as Tina.
- Buffy the Vampire Slayer and Angel:
- Tom Lenk, known for playing Andrew in the evil geek trio during Buffy's sixth season (and beyond), originally appeared in a bit part as one of Harmony's vampire minions.
- Andy Hallett, best known as Lorne from Angel, was originally an extra in the Buffy episode "Hush".
- CSI Verse: CSI: NY regulars Carmine Giovinazzo and A.J. Buckley had each previously appeared in a one-off role in original-flavor CSI.
- Jeff's nephew, also a nurse, in Casualty was played by someone who had previously played two different one-shot characters (which both had large parts in their episodes). These one-shots were quite recognisable, though, because the actor had been in the Doctor Who spin-off The Sarah Jane Adventures at the same time as them and is quite memorable in appearance.note
- Charmed: Rebecca Balding, who plays Phoebe's newspaper boss Elise, was the aunt of a young witch in the Season 1 episode "The Fourth Sister".
- CHiPs. Randi Oaks played a car thief named Kim Balford in the Season 2 episode "Down Time" and joined the cast as officer Bonnie Clark at the beginning of Season 3.
- Community has two examples in their Final Season Casting:
- Keith David narrated the Season 3 episode "Pillows And Blankets" before taking the role of Season 6 cast regular Elroy Patashnik.
- Paget Brewster appears in the Season 5 episode "Analysis of Cork-Based Networking" as IT Admin Debra Chambers before taking the role of Season 6 cast regular Frankie Dart. They addressed this once when Frankie tried to contact IT support but her e-mails all got bounced back, and when she tried to call Debra on the phone she only managed to hear chanting in Aramaic.
- Dallas:
- Barbara Stock, who portrayed Cliff's love interest Liz Adams in the final season, originally played an unrelated character Heather Wilson in two episodes in Season 5.
- Tracy Scoggins played a call girl named Dianne in the seventh-season episode "My Brother's Keeper", and then returned to play Anita Smithfield in J.R. Returns.
- Brenda Strong had a role in a tenth-season episode of the original series as one of Cliff's one night stands before being cast as Bobby Ewing's new wife Ann in the 2012-2014 Sequel Series.
- Mitch Pileggi (who plays Ann's ex-husband, Harris Ryland), in addition to being an extra in a very early episode in the '80s, had a three-episode role in the original series as a mental patient who bullied J.R. when he was in a mental institution.
- Glenn Morshower (who plays Lou, a lawyer who helps the Ewings throughout the first season) played a small role as a campaign aide in the original series' first-season episode "Black Market Baby".
- In the revival, Sam Anderson plays a recast of Dr. David Gordon (who was established as Pam's doctor/pretend fiancee in the last episode featuring her in the original series), while in the original series he played a detective during Season 8 who helped Bobby prove Jenna innocent of murder.
- In Dark Angel Jensen Ackles played guest character Ben in a season 1 episode and was later recast as Ben's twin brother Alec, a regular character in season 2.
- Deadwood: Garret Dillahunt played the coward Jack McCall on the first season, then came back the next season to play Francis Woolcott. McCall was, however, featured in five episodes, and was a very memorable character, which is probably why Dillahunt grew a beard for playing Wolcott, to lessen the visual similarities between the two characters.
- Death in Paradise: Ralf Little appeared as holidaymaker Will Teague before being cast as DI Neville Parker in series 9 to replace Ardal O'Hanlon's Jack Mooney.
- Doctor Who and the Whoniverse have several examples:
- Jean Marsh played Richard the Lionheart's sister in "The Crusade" before becoming one of the Doctor's travelling companions in "The Daleks' Master Plan". Decades later, she played the villain in "Battlefield".
- Peter Purves played two different characters in the same serial ("The Chase") Fake American Morton Dill and new companion Steven Taylor.
- Nicholas Courtney played a character called Bret Vyon for four episodes of "The Daleks' Master Plan", before returning three years later to play The Brigadier until his death.
- John Levene first appeared in the Patrick Troughton-era episodes "The Abominable Snowmen" and "The Web of Fear", and then appeared as UNIT soldier Sgt. Benton in "The Invasion", becoming a regular cast member for most of the Jon Pertwee era. A bit less noticeable than other examples, as in the first two stories he was dressed in a Yeti suit.
- Ian Marter played Lieutenant Andrews in "Carnival of Monsters" before joining the regular cast as Harry Sullivan.
- In "The Armageddon Factor", Lalla Ward played Princess Astra whom Romana liked so much that she modelled her next regeneration on her.
- In an inversion, Jacqueline Hill, who played original companion Barbara Wright, later returned as the Tigellan Lexa in "Meglos".
- Colin Baker guests in "Arc of Infinity" as Commander Maxil, an antagonist of the Fifth Doctor, about two years before being cast as Doctor No. Six.
- Eve Myles played Gwyneth in "The Unquiet Dead", and then became a future relative of that character as Torchwood lead Gwen. In "Journey's End", an In-Universe explanation of "spatial genetic multiplicity" (the Cardiff Rift copied Gwyneth's appearance onto Gwen) was given.
- Adjoa Andoh played Sister Jatt in "New Earth", and then was cast as Martha's mother Francine, in another example obfuscated by heavy makeup.
- It runs in the Jones family, as Freema Agyeman, who plays Martha Jones, previously appeared as Torchwood tech Adeola Oshodi. This one is explained away by Martha herself she mentions that she had a cousin named Adeola, thus it's a Strong Family Resemblance.
- Paul Marc Davis played Chiefs in both Doctor Who and Torchwood before becoming the Trickster.
- Peter Capaldi, the Twelfth Doctor, first appeared as the Roman nobleman Caecilius in "The Fires of Pompeii". He also had a prominent role as John Frobisher in the spinoff Torchwood: Children of Earth. This is addressed In-Universe following his regeneration, and in the episode "The Girl Who Died". In the latter, the Doctor sees it as his reminding himself that he can save people even when all hope seems lost.
- The official In-Universe explanation for the resemblances: The face is originally Caecilius'. Frobisher is a direct descendant, and the 12th Doctor subconsciously copied his appearance for the reasons mentioned above.
- Karen Gillan became regular companion Amy Pond two years after playing a cult priestess in "The Fires of Pompeii", the same episode that featured Capaldi.
- Dan Starkey has been playing random Sontaran warriors since the return of the series, then was cast as recurring character Strax. Notably, this means he has played two different lead characters at the BBC Doctor Who Proms (Skorr which he played in two 2008 episodes and Strax). Those are two of three different speaking Sontaran parts he's had (the other being Jask. He has, though, played different extra roles even after starting as Strax, because of the reasonable anonymity afforded him for all the Sontaran makeup: another random Sontaran warrior in an episode without Strax, and Ian in "Last Christmas".
- Neve McIntosh played Silurian sisters Alaya and Restac in 2010, and from 2011 onwards she played Madame Vastra, the Silurian detective.
- Pooky Quesnel played a spaceship captain in "A Christmas Carol", and then Dorothea Ames in the short-lived Class.
- David Bradley played a Villain of the Week on "Dinosaurs on a Spaceship", five years before becoming the official actor for the First Doctor in the revival era, playing him in "Twice Upon a Time". He also played William Hartnell in the 50th anniversary docudrama An Adventure in Space and Time.
- Bradley Walsh played the Pied Piper and his alter-egos, Odd Bob and Elijah Spellman, in The Sarah Jane Adventures story "The Day of the Clown" before being cast as Thirteenth Doctor companion Graham O'Brien.
- In another inversion, Anjli Mohindra, who played Rani Chandra on The Sarah Jane Adventures, guest-starred as the Queen of the Skithra in series 12 episode "Nikola Tesla's Night of Terror", although once again under such heavy make-up that only people who read the cast list would know.
- ER:
- J.P. Manoux played an unnamed mime in a 1996 episode, then was cast as Dr. Crenshaw a full decade later.
- Vondie Curtis Hall appeared as a transvestite in S1. He reappeared a few seasons later as a recast version of Roger, stepfather to Benton's son.
- Justina Machado appeared as a one-off character in a 1997 episode ("Ambush"). Twelve years later, she returned as recurring character Claudia Diaz, who ends up dating (and, it is stated, eventually marrying) Dr. Archie Morris.
- Troy Evans appeared as an unnamed cop being treated by Carter in the pilot episode, before returning in a recurring role as desk clerk Frank from Series 6 onwards. It was established that Frank was an ex-cop, so they could conceivably have been the same person.
- Everybody Loves Raymond. Before becoming Ray's lazy, sports-obsessed pal Giani, Joe Manfrellotti appeared in Season One's "The Game" as a cable repairman who discovers an illegal splitter sending cable to Frank and Marie's house.
- Farscape: Melissa Jaffer joined the regular cast in Season Four as Noranti after playing two guest parts in different episodes of the second season: the older version of Nilaam in "Vitas Mortis", and the voice of the female Pilot in "The Way We Weren't".
- Frasier:
- Friends:
- Giovanni Ribisi played a teenager who accidentally dropped a condom in Phoebe's guitar case, about half a season before he was cast as Phoebe's half-brother.
- June Gable played a nurse in episode 23 before picking up a recurring role as Joey's agent Estelle. According to her, she was always meant to be Estelle, but her scenes were cut from that episode and she was given the part of the nurse to make up for it.
- Jennifer Coolidge and Adam Goldberg guest starred on Friends. Both ended up in regular roles on Joey; the latter, though, was more of a recurring role.
- Future Cop contains a particularly confusing example. Herbert Nelson plays an important scientist in the pilot but plays Captain Skaggs for the rest of the series.
- In Game of Thrones, Dean Charles Chapman played the small role of Martyn Lannister in Season 3 before taking over the role of Tommen Baratheon in Season 4, making for a case of an actor being both The Other Darrin and Recast as a Regular. While this isn't addressed in the series itself, Tommen and Martyn are actually first cousins (once removed) in a family wrought with Kissing Cousins and BrotherSister Incest, so this could be used to explain the strong resemblance.
- The Gene Autry Show has a rather unusual example: despite Pat Buttram being Gene Autry's sidekick from the beginning of the series, Buttram didn't officially become sidekick as himself until the second season, and through the first half of the first season, he played two Danza sidekicks named Pat Jensen and Patrick Smith, and one sidekick named Hap Wallace. Similarly, prior to the TV series, Buttram also played different sidekicks or other allies to Autry in a few of his movies in place of Autry's original regular sidekick Smiley Burnett.
- A first-season episode of The Golden Girls featured Harold Gould as Rose's date, Arnie, long before he became a recurring character as Rose's steady boyfriend Miles.
- Green Acres. Before becoming half of Hooterville's carpentry company - Alf and Ralph - Sid Melton appeared in one of the earliest episodes in a rather similar role as one of the potential interior decorators Oliver was looking to hire to help redecorate the Old Haney Place.
- Happy Days:
- In season two, Linda Purl played Richie's recurring girlfriend Gloria, while in season 10 she played Fonzie's girlfriend Ashley Pfister.
- Lynda Goodfriend was cast as Richie's date Kim a good while before being brought back as his girlfriend-turned-wife Lori Beth Allen in season five.
- In season 9, Crystal Bernard guest starred in "The Telltale Tart" before joining the cast in season 10 as KC Cunningham.
- On Hawaii Five-O, Al Harrington played assorted bad guys in five episodes over the show's first four seasons before becoming a Five-O regular (as Ben) in Season Five.
- Conchata Ferrell played the main character's ex-wife's lesbian lover in one episode of the first season of Hearts Afire, but she joined the series as a regular in the second season, playing straight-as-an-arrow Madeline. Both characters were therapists but otherwise had no connection.
- Hill Street Blues: Dennis Franz appeared in several episodes as a crooked cop named Sal Benedetto. One or two years later he reappeared as the non-crooked but otherwise identical character Norman Buntz.
- Hogan's Heroes.
- Larry Hovis is a variation of this. Although he played Carter in the pilot, this Carter was different than his series' proper Carter: the Carter in the pilot was a lieutenant instead of a sergeant and was an escapee who was being passed through Stalag 13 on his way to rejoin his unit in London. This Carter was intended to be a one-shot guest character, but when Leonid Kinsey (Vladimir) refused to sign on as a regular when the pilot went to series, Hovis was brought back to play Carter as Hogan's young, bright-eyed, yet naive explosives expert and bomb-maker.
- Howard Caine played two different German officers in two different episodes before becoming a semi-regular as Major Hochstetter in Season Three. One appearance was in "Happy Birthday, Adolf" from Season One, playing a Major who was involved in organizing a party for Hitler's birthday while remaining on alert for an impending American air raid; in "The Battle of Stalag 13" from Season Two he played a Colonel wanting to turn Stalag 13 into a camp for local citizens to be interrogated for suspicious activity (ironically, the character wore the exact same uniform as that of Major Hochstetter).
- Patricia Olsen, otherwise known as Sigrid Valdis, played a fraulein General Burkhalter uses in a Season One episode to soften up Hogan to get information from him before becoming Klink's second secretary Hilda the following season for the remainder of the series.
- Jon Cedar is an inversion: despite playing Klink's guard Langenscheidt from the beginning, he appears in two other random roles, one of which is a German counterfeiting expert, the other a rookie Gestapo officer who cracks after enduring nonstop abuse from his superior.
- Cynthia Lynn is another inversion: after leaving the show after its first season, in which she played Klink's first secretary Helga, she made two random guest appearance as different characters seasons later.
- On Home Improvement, Debbe Dunning played a one-off role in the season two episode "Overactive Glance" before she started playing Heidi in season three.
- On Homicide: Life on the Street, Walt McPherson played a uniformed officer in the first season who finds a piece of evidence. He appears later, starting in the third season, in a recurring role as homicide detective Roger Gaffney. Gaffney rises from detective to lieutenant to captain.
- I Dream of Jeannie. Before becoming Dr. Bellows's wife Amanda, Emmaline Henry appeared in the Season One episode "Is There an Extra Genie in the House?" as the sexy assistant to a down-on-his-luck magician who temporarily rent out Roger's apartment.
- I Love Lucy. Frank Nelson was a frequent guest star on a number of episodes throughout the first five seasons, including such notable appearances as Freddy Filmore, a local radio emcee, and a Hollywood talent scout who launched Ricky's would-be film career. During the final season, Nelson was cast in a permanent recurring role as Ralph Ramsey, the Ricardos' neighbor in Connecticut and a TV producer who helped Ricky gain a little more exposure to a broader audience.
- Two main protagonists in Inspector Rex (Brandtner and Hoffmann) were played by actors who had appeared before as villains of the week in earlier seasons of the show. Elke Wilkens played a minor character in season 7 before acting as Nikki Herzog.
- JAG/NCIS:
- Catherine Bell was originally cast as Harmon Rabb's girlfriend who is murdered in a first-season episode of JAG, which never aired during the U.S. network run due to cancellation of the show by NBC. When CBS picked up the series, Bell was cast as the new female lead Sarah "Mac" Mackenzie. Harmon Rabb acts like he's seen a ghost when she is introduced to him, and we later learn why in a Whole Episode Flashback incorporating the original episode.
- Sean Murray first appeared on JAG as a one-shot character named Ensign Terry Guitry; he then had a five-episode arc as Danny Walden a couple of years later. A few years later, he joined its NCIS as Special Agent Timothy McGee.
- Michael Bellisario played two minor roles on JAG before being cast as major recurring character Mikey Roberts, then also appeared on 4 episodes of NCIS as Chip Sterling, Abby's assistant.
- Kamen Rider:
- Makoto Akatsuka was in episode 28 of Kamen Rider BLACK as the kid of the week's father. In Black's direct sequel, Black RX, he had a bigger role of Kotaro's foster dad, Shunkichi Sahara.
- Kamen Rider Kiva: Shoma Yamamoto first appeared in The Movie as the antagonist Takato Shiramine (Kamen Rider Rey). Reportedly, the staff liked his performance so much that he was cast in the TV series proper as Taiga Nobori (Kamen Rider Saga), a major character in the latter half of the show and also the protagonist's long-lost older brother. Interestingly, Rey and Saga even have the same color scheme. Despite that, they're very different characters.
- Law & Order has several examples:
- Jerry Orbach first appeared on Law & Order as a one-off character, a defense lawyer, before later being cast as Lennie Briscoe.
- Raúl Esparza appeared as the perp of the week in an episode of Law & Order: Criminal Intent before becoming ADA Rafael Barba on Law & Order: Special Victims Unit. Ironically, his Criminal Intent character was also a prosecutor (albeit a corrupt one).
- Michelle Hurd appeared in a minor part in an episode of L&O before being cast as Monique Jeffries on SVU.
- Ice-T appeared in Exiled, the franchise's Made-for-TV Movie, before being cast in the regular role of Detective Fin Tutuola on SVU.
- Melissa Sagemiller made her acting debut in the first season of SVU before being brought back in Season 12 as their main ADA, Gillian Hardwicke.
- Courtney B. Vance played a Scary Black Man in an episode of L&O before being cast as ADA Ron Carver on CI.
- Alfred Molina played a perp of the week on the SVU and Law & Order: Trial by Jury Crossover before being cast as Deputy DA Ricardo Morales on Law & Order: LA.
- Kelli Giddish appeared as a one-off suspect in Law & Order: Criminal Intent episode "Depths" before later joining the main cast of SVU as Detective Rollins. She also appeared as a Victim of the Week in the SVU episode "Outsider"; in fact, she was interviewed after the assault by Fin Tutuola, who would become Rollins' regular partner.
- Joanna Merlin played two minor characters in Law & Order, in a total of five episodes, before becoming the regularly recurring judge Lena Petrovsky in SVU.
- David Thornton played four different one-off characters in the original series, before being cast as recurring defense attorney Lionel Granger in SVU.
- Ned Eisenberg played two one-off characters on SVU before being cast as one of the most common defense attorneys, Roger Kressler. This also overlapped in time with stints as two one-off characters on Criminal Intent and a rare recurring attorney on the original Law & Order.
- Elizabeth Marvel played four different one-off characters across the three main series before becoming recurring defence attorney Rita Calhoun in SVU.
- S. Epatha Merkerson had a small one-off role as a cleaning lady in the first season of Law & Order, then was cast as Lt. Anita Van Buren beginning in season four.
- Tamara Tunie guest-starred on a Season 7 episode of the parent series before being cast as SVU regular Dr. Melinda Warner.
- Jeremy Sisto played a one-off role as a defense lawyer in the final episode of season 17 before making his debut as Detective Cyrus Lupo one episode later in the first episode of season 18.
- Diane Neal, who played ADA Casey Novak in seasons 5-9 of SVU, previously appeared as a rapist and murderer two seasons earlier.
- Isabel Gillies appeared as a Villain of the Week in a Season 8 episode of the mothership before being cast as Kathy Stabler, wife of Det. Elliot Stabler, in SVU.
- Anthony Anderson appeared as a different cop on SVU before being cast as Detective Kevin Bernard in Law & Order.
- Annie Parisse had a one-off role a few years before becoming a regular as ADA Alexandra Borgia.
- Milena Govich had a one-off role on Law & Order preceding two regular roles in the franchise: first as ADA Jessica Rossi in the short-lived Conviction, then back in L&O as Detective Nina Cassaday.
- Julianne Nicholson had a one-off role on the parent series before being cast as Det. Megan Wheeler on Law & Order: Criminal Intent.
- Annabella Sciorra played a defense lawyer in Law & Order: Trial by Jury before being cast as Carolyn Barek on Law & Order: Criminal Intent.
- Bebe Neuwirth appeared as a one-shot character in Law & Order: Special Victims Unit. Six years later she was cast as EADA Tracey Kibre, the lead character on Law & Order: Trial by Jury.
- Amy Carlson appeared as one-shot characters in both SVU and the parent series before being cast as ADA Kelly Gaffney on Law & Order: Trial by Jury.
- Kirk Acevedo appeared as one-shot character in the parent series before being cast as Det. Hector Salazar on Law & Order: Trial by Jury.
- Scott Cohen appeared as a three-episode guest character in the parent series before being cast as Det. Chris Ravell on Law & Order: Trial by Jury.
- Eric Bogosian appeared as a defense attorney in two episodes of the early L&O seasons, more than a decade before he started out as Cpt. Danny Ross in Law & Order: Criminal Intent.
- Jay O. Sanders played a Killer-Of-The-Week in one episode of Criminal Intent before playing Cpt. Hannah in the final season.
- Corey Stoll appeared as one-shot character in the parent series before being cast as Det. Tomas Jaruszalski on Law & Order: LA.
- Peter Scanavino had four unrelated guest appearances across the franchise (one each on Trial By Jury, Criminal Intent, the original, and SVU, in that order) before being cast as Sonny Carisi in SVU.
- Edie Falco played minor Recurring Character Sally Bell in the original series before being cast as Leslie Abramson, the main lead of Law & Order: True Crime, nearly two decades after her original character's final appearance.
- MacGyver:
- Dana Elcar appeared in the pilot episode as Andy Colson, the guy manning the control room while MacGyver does his mission. Later in the season, he was cast as Pete Thornton, Mac's close friend, boss and only other person in the intro.
- Elyssa Davalos appears as a (presumably) Baltic love interest of MacGyver in the two-part S3 opener. Less than a month later, she appears again as Nikki Carpenter and appears in four further episodes.
- Magnum, P.I.:
- Lance LeGault appeared as Delta Agent John W. Newton, then returned as recurring character Colonel Buck Greene for several episodes.
- Kathleen Lloyd played a client of Magnum's then returned as recurring character D.A. Carol Baldwin for several seasons.
- Married... with Children: Ted McGinley appeared in the Season 4 Christmas Episode "It's a Bundyful Life" as Peggy's "alternate history" husband, before joining the regular cast as Jefferson D'Arcy the following season.
- M*A*S*H.
- Harry Morgan played a nutty U.S. Army General in the 3rd season episode "The General Flipped at Dawn". He did such a good job that in the 4th season he was cast in the role of the 4077th's new commanding officer, Colonel Sherman Potter, which he played for the remainder of the series.
- Richard Lee Sung once appeared as a generic Korean local (specifically, one of five Kim Luck's the hospital treated in one day) before becoming Cho Man Chin, the local peddler who would, at least Once a Season, try to swindle folks at the 4077th by selling them crooked goods such as wristwatches that ran backwards, wild boar tusks that are really plastic, and 2x4s that used to be round.
- John Orchard is an inversion of this. Throughout the first season, he played Ugly John the camp anesthesiologist, but was eventually written off the show when the production staff felt there were too many minor characters to keep writing for. Orchard eventually returned in a guest role in Season Eight as an Australian M.P.
- Edward Winter may or may not count, depending on which word you believe. In his first appearance, Winter played an overzealous Intelligence officer named Captain Halloran, and all subsequent appearance he played his noted character Colonel Samuel Flagg; while there is only a slight difference in the characters' demeanor (Halloran was easily convinced to drop everything and join in a poker game), knowing how Flagg frequently uses very many different aliases, one common theory among fans is that Halloran was one of his aliases. That theory is helped by a later appearance in which Flagg reminds Sidney Freedman they played poker once.
- Before becoming the last and final Rosie of Rosie's Bar, Eileen Saki appeared in a memorable guest role in Season Five's "Bug Out, Part 2" as the leader of a ring of Korean prostitutes that lived in an abandoned schoolhouse.
- Many of the actors who became regulars on Matlock initially appeared before in different episodes.
- Martin Ferrero appeared in the Miami Vice pilot as a cross-dressing hitman and went on to play the recurring snitch Izzy Moreno.
- Midsomer Murders: When Tom Barnaby's actor left the show, they replaced him with his cousin John Barnaby, whose actor had appeared earlier playing a sleazy but innocent suspect who hit on Barnaby's wife.
- Mork & Mindy. Jonathan Winters appeared as Dave McConnell (Mindy's uncle) in a third season episode. He was cast as Mork and Mindy's child Mearth starting in the fourth season.
- The final episode of the first season of Murder, She Wrote, "Funeral at Fifty-Mile", featured William Windom as one of the suspects, a lawyer named Sam Breen. Season 2 introduced recurring character Dr Seth Hazlitt, also played by William Windom, who would go on to appear in more episodes than any other character except Jessica herself.
- NewsRadio: Jon Lovitz appeared on two episodes as two different characters before being cast as Max Louis in the fifth and final season.
- New Tricks: Tamzin Outhwaite replaced Amanda Redman as the squad boss for the last episodes, after having already appeared as a suspect long before. The guilty suspect, no less.
- NUMB3RS: Sophina Brown, who began playing Agent Nikki Bentencourt in Season 5, had a one-scene appearance as an environmental activist in a Season 2 episode.
- The Odd Couple. Pamelyn Ferdin appeared in the Season One episode "Bunny is Missing Down by the Lake" as a member of an all-girl camp group who seeks shelter from the rain at the cabin Felix and Oscar stay at before becoming Felix's daughter Edna the following season.
- Power Rangers:
- Tracy Lynn Cruz was an extra in Mighty Morphin' Power Rangers Season 3's Christmas Special, I'm Dreaming of a White Ranger, before getting cast as Ashley Hammond, the Yellow Ranger of two consecutive seasons.
- James Napier was cast as Eric, a Last Episode, New Character in Ninja Storm's finale, before getting cast as Conner, the Red Ranger, of Dino Thunder. Conner eventually mentioned a brother who'd washed out of the Wind Ninja Academy.
- Dwayne Cameron first appeared in Dino Thunder as Derrick, the titular "Bully For Ethan", then in SPD as Monster of the Week Dru Harrington/Giganis. He was then cast as Tyzonn, the Mercury Ranger, in Operation Overdrive.
- Jarred Blakiston played a Spear Carrier in Megaforce episode 4, Stranger Ranger, before appearing as Prince Phillip, the Graphite Ranger, in Dino Charge.
- John Larroquette guest-starred several times on The Practice as Magnificent Bastard Joey Heric. A few years later, he became a regular on the show's spin-off, Boston Legal, playing senior partner Carl Sack.
- On Quincy, M.E., Anita Gillette played Quincy's late wife in a flashback in "Promises to Keep". In 1982, she joined the cast as Emily Hanover ... who married him.
- Red Dwarf: Hattie Hayridge first appeared as the computer 'Hilly' in the episode "Parallel Universe", then took over as Holly from series 3-6, which was Handwaved with the suggestion that Holly had remodelled himself to resemble Hilly.
- Sabrina the Teenage Witch:
- Bumper Robinson appeared in Season 1's "Trial By Fury" as Clifford Weaver, before getting cast as James in Season 7.
- John Ducey played Mr. Kraft's nephew in Season 3's "The Band Episode", before also reappearing as a regular in Season 7 (Leonard).
- A variation with Tara Strong. She voiced the Molly Dolly in Season 3 before getting cast as a protagonist Gwen in the two spin-off movies.
- Sanford and Son. Before playing Woody and Esther's adopted teen son Daniel at the beginning of the final season, Eric Laneuville appeared in the Christmas Episode "Ebenezer Sanford" as a local teen who asks Fred to put him to work so he can earn at least enough money to buy his parents a Christmas present.
- The Sopranos: Joseph R. Gannascoli, who played Vito Spatafore for much of the series, initially appeared as a completely unrelated minor character in a season 1 scene where Christopher goes ballistic on a pizzeria clerk.
- Stargate-verse:
- Paul McGillion, who played the main/recurring character Carson Beckett on Stargate Atlantis, had previously played a young Ernest Littlefield, the first 20th century human to use the Stargate, in flashbacks in the first season of Stargate SG-1.
- In Atlantis, Jewel Staite plays a Wraith in season 2's "Instinct". In season 4 she returns as Dr. Keller.
- Peter Kelamis played a scientist and an alien news anchor, Mark Burgess played Wraith's victim before they became recurring Stargate Universe characters.
- Star Trek.
- Majel Barrett was cast as the nameless "Number One" officer in the original pilot, "The Cage", before being cast as recurring character Christine Chapel in Star Trek: The Original Series, Lwaxana Troi in Star Trek: The Next Generation and Deep Space Nine, and the voice of Federation starships from TNG onwards. note
- Diana Muldaur was a guest star in two Star Trek: The Original Series episodes (in different roles) before becoming the regular Dr. Pulaski in Star Trek: The Next Generation's second season.
- Mark Lenard did a one-off as a Romulan Commander in the TOS episode "Balance Of Terror" before becoming beloved recurring guest star Sarek beginning in "Journey To Babel".
- Tim Russ did guest roles in TNG, Star Trek: Generations and DS9 before becoming Tuvok on Star Trek: Voyager. Ironically, the actor for the TNG era's only Vulcan regular once got the Vulcan nerve pinch applied to him by Picard (who is theorized to have learned it from mind-melding with Sarek or later Spock in their previous guest appearances.) Also, some time after Generations, there was a flashback episode about Tuvok on the Excelsior under Sulu, meaning Tuvok and his other lookalike were both Starfleet officers at the same time on ships of the same class.
- Jeffrey Combs has appeared in several Star Trek: Deep Space Nine and VOY roles both before and after his main role as recurring DS9 villain Weyoun. In Star Trek: Enterprise he was cast as the Andorian Captain Shran, an uneasy ally of Captain Archer. Supposedly, he was supposed to join the cast as a regular in the fifth season had it been made.
- René Auberjonois was Colonel West in Star Trek VI: The Undiscovered Country before becoming Odo in DS9.
- Salome Jens was the humanoid precursor in the TNG episode "The Chase" before being cast in the recurring role of the female changeling in DS9.
- Robert Duncan McNeill guest starred as Starfleet cadet Nicholas Locarno in the Star Trek: The Next Generation episode "The First Duty". The writers of Star Trek: Voyager wanted to use the character as a regular, but the possibility was raised that this would have required paying royalties to the writers of "The First Duty" for every episode the Locarno character appeared in, so in order to avoid the potential issue, they created a "new" character named Tom Paris instead and cast McNeill in the role.
- In the Star Trek: The Next Generation season 1 finale "The Neutral Zone", Marc Alaimo guest-starred as Commander Tebok, the first TNG-era Romulan. In the season 4 episode that introduced the Cardassians, "The Wounded", Alaimo guest-starred as the Cardassian leader Gul Macet. When the Cardassians' role was expanded for Star Trek: Deep Space Nine, the producers wanted Alaimo back, but the Macet character was too nice a guy to make a good villain, so they removed his truly unfortunate facial hair and named the new character Gul Dukat. The Expanded Universe explains the resemblance by making them cousins (and the facial hair, otherwise nigh-unknown on Cardassians, as something Macet grew specifically so he would look less like Dukat).
- Michelle Forbes had a role in Season 4 of TNG in "Half a Life" as an "Alien of the Week", before returning in Season 5 as semi-regular character Ensign Ro. Forbes was approached to play Ro as a main character on both DS9 and Star Trek: Voyager, but she was not interested in a series-long commitment, resulting in the creation of Major Kira Nerys and Lt. B'ellana Torres.
- Armin Shimerman played a Betazoid gift box and two Ferengi in TNG before becoming Quark in Deep Space Nine.
- Max Grodenchik played a couple of Ferengi in TNG before becoming known as the semi-regular character Rom in Star Trek: Deep Space Nine.
- Ethan Phillips played a Ferengi in the TNG episode "Menage a Troi" before playing Neelix on VOY. In the episode " False Profits", Neelix disguises himself as a Ferengi. Gee, wonder where they got that idea.
- James Cromwell played a number of one-off characters throughout the franchise, both human-like and alien. But his role as Zephram Cochrane in Star Trek: First Contact, the inventor of warp drive and the one to establish humanity's first contact with aliens, making him a major player in the Star Trek lore despite the limited appearances. He does reprise the role in certain episodes and stock footage.
- Robert O'Reilly played the holographic character "Scarface" in the TNG episode "Manhunt" before receiving the recurring role of Klingon Chancellor Gowron starting with the episode "Reunion" and continuing through DS9.
- Super Sentai:
- Hirohisa Nakata played a minor EAGLE officer in episode 33 of Goranger and minor villain Dellinger in episode 28 of Denziman, but is best remembered as Mason in Bioman.
- Nobuo Yana appeared as Dr. Shinigami (Not that one.) in Goranger episode 53, and returned three episodes later to take over from Mitsuo Ando as The Black Cross Fuhrer. Episode 53 also had Ichirō Nagai as Baseball Mask. Nagai later voiced the also baseball themed Devil Batter in JAKQ, and would later voice Gekiranger's Big Good, Master Xia-Fu.
- Zigzagged with Machiko Soga. Her first Sentai role was in Battle Fever J episode 3 as the Monster of the Week Death Mask Monster, followed by Denziman's Big Bad Queen Hedrian. Her next appearance was as Laraba in Maskman episode 30. That was followed by her role as Zyuranger Big Bad Bandora (and by proxy, Rita Repulsa) and Magiranger Big Good Magiel.
- In Battle Fever J, Masashi Ishibashi played the Psychokinesis Monster in Episode 4, then came back to play General Hedder starting with episode 9 after Kenji Ushio was arrested early on. Ushio's episodes (save for 4 and 6) were reshot with Ishibashi. Ushio himself had guest spots in Goranger and JAKQ with his most substantial role being Baron Iron Mask in JAKQ vs Goranger. Ishibashi played Baron Iron Claw in JAKQ and later appeared as Dynaman's General Kar and Turboranger's Doctor Lehda.
- Takao Yamada played Sabu, one of a trio of thieves in Denziman episode 30. He then appeared in the next season, Sun Vulcan as supporting character Sukehachi Yazawa. Episode 26 also featured Ryusei Nakao in a live-action role as Gou Koyuki. His next Sentai role came twenty-four years later as Dekaranger Big Bad Agent Abrella.
- Satoshi Okita guest starred as Hideo Komura in episode 10 Goggle Five, then played Dyna Red/Hokuto Dan in Dynaman.
- Strong Kongou played the good android Gon in episode 35 of Dynaman, then the evil, yet dumb android Monster in Bioman.
- Flashman had two guest stars who played more significant roles in the next season, Maskman. Ryousuke Kaizou (Ryu Wakasa in episode 27) went on to play Takeru/Red Mask, while Mina Asami (Shibehl in Episode 40) went on to play Prince Igam and Princess Ial.
- Maskman also featured two guest stars with higher profile roles in the next season. Kazuhiko Nishimura (Kurokawa in episodes 28-29) played Joh Ohara/Yellow Lion, while Toru Sakai (Shinya in episode 32) played Doctor Obular.
- Turboranger featured two future rangers as one-shot characters. Sayuri Uchida (Yumi in episode 9) went on to play Ako Hayasaka/Blue Swallow, while Ryo Narushima/Keiko Hayase (Mika Yamaguchi in Episode 37) went on to play Remi Hoshikawa/Five Yellow.
- Two guest stars in Jetman played two of the heroes of the next season, Zyuranger. Yuta Mochizuki (G1 of the Neo Jetman) played Geki/Tyrannoranger, and Hideki Fujiwara (Dan the Birdman) played Dan/Tricera Ranger.
- In Zyuranger, Hisashi Sakai played young Burai in flashbacks. He soon played the next Sixth Ranger, Kou, in Dairanger. Maroshi Tamura, who played Zyuranger Monster of the Week Dora Franke, appeared as Dairanger villain Zaidos. Shin Nagahama played Episode 39's kid of the week, Hirata, 22 years before he played ToQger's Sixth Ranger, Akira Nijino/ToQ 6gou.
- Yoshihiro Fukuda appeared in episode 36 of Dairanger as a mountain climber, then made a return trip to the series three years later as Minoru Uesugi/Green Racer in Carranger.
- Satoru Saito had a few roles of increasing importance. He was Dairanger Monster of the Week General Cactus, Bumbling Dad / Butt-Monkey Ichiro Nitta in Ohranger and finally, Megaranger Mentor Dr. Kubota.
- On Supernatural:
- Ty Olsson plays Benny, a vampire who's been an ally to Dean. He previously played a completely different vampire in an episode way back in season 2.
- Erica Carroll initially played a nurse in a one-off role in an early season, and then was brought back playing an angel named Hannah in season 9.
- Tyler Johnson played a kid in season 1 episode Bugs, and then later played recurring angel Samandriel.
- Two and a Half Men: Jennifer Bini Taylor had multiple cameos as minor characters before being cast as Charlie's long-time fiancee Chelsea Melini.
- In Season 2 of Veronica Mars, James Jordan appeared as the mentally unstable janitor Tommy "Lucky" Dohanic for a few episodes, then reappeared in Season 3 as recurring character Tim Foyle, the graduate student of Dr. Landry.
- In The Wire, Gbenga Akinnagbe was an extra as a random police officer standing in a courtroom in Episode 4 of Season 1. Years later he would return and from Season 3 until the end of the show he played Chris Partlow, The Dragon and coldly efficient chief assassin/enforcer for sociopathic druglord and mass murderer Marlo Stanfield.
- The X-Files: Nicholas Lea appeared in an early episode "Gender Bender" playing a character named Michael, then returned later as series regular Alex Krycek.
- Young Sheldon: Lance Barber, the actor who plays George Cooper (Sr.), previously appeared in parent show The Big Bang Theory as Jimmy Speckerman, Leonard's childhood bully, in the episode "The Speckerman Recurrence".
- Zoey 101: Austin Butler, before being cast as James (one of the main characters in season 4), portrayed Stacey's boyfriend Danifer in the season 3 episode "Quarantine".
- Sesame Street. Michael Jeter made a couple of guest appearances on the show in the late 90s, including his own version of the classic song "Dance Myself to Sleep"
before being cast as Mr. Noodle's Brother Mr. Noodle while Bill Irwin (Mr. Noodle) was busy filming How the Grinch Stole Christmas!.
- In the Finnish version of The Men from the Ministry both Heikki Nousiainen and Antti Pääkkönen had several minor roles in multiple episodes before being cast as Lennox-Brown and Sir Clive, respectively.
- In the Batman: Arkham Series, Matthew Mercer had a minor role in Batman: Arkham Origins as the villain Anarky for one of the side missions. The next game, Arkham Knight, had him take over as Tim Drake, one of the heroes and playable characters in the game.
- In the English dub of Bravely Default Michael Sinterniklaas provided the voice of Jackal, one of the bosses required to get one of the job classes for the game. For the game's sequel, Bravely Second, he portrayed the main protagonist, Yew.
- Jess Harnell, the current voice of Crash Bandicoot, had previously voiced Lo-Lo the Air Elemental in Crash Bandicoot: The Wrath of Cortex prior to becoming Crash.
- Avatar: The Last Airbender: Before voicing main character Toph, Jessie Flower voiced Meng from "The Fortuneteller".
- DC Animated Universe:
- On Batman: The Animated Series, before playing the Joker, Mark Hamill played the role of the Corrupt Corporate Executive that was responsible for Victor Fries's accident. This example crosses over with The Other Marty, as Joker had already had voice work recorded by Tim Curry, but it had to be replaced because doing so hurt his throat.
- Ron Perlman, who voices Clayface, also voiced a random thug (called "Driller") in the episode "P.O.V."
- Carl Lumbly had a couple of guest spots in Superman: The Animated Series and voiced Stalker on Batman Beyond before voicing the Martian Manhunter in Justice League.
- Dana Delany provided the voice of Bruce Wayne's love interest Andrea Beaumont in Batman: Mask of the Phantasm before going on to do the voice of Lois Lane for Superman: The Animated Series and Justice League.
- Sherman Howard voiced the Perserver and Steppenwolf in Superman: The Animated Series before being cast as Derek Powers in Batman Beyond.
- Michael Rosenbaum provided the voice of Ghoul for the film Batman Beyond: Return of the Joker, and Terminal in Beyond proper before later getting cast as The Flash for Justice League.
- The opening of Batman Beyond's first episode "Rebirth" saw C.C.H. Pounder as a reporter — years before Justice League Unlimited cast her as Amanda Waller.
- The JLU episode "Dark Heart" had Michael Beach as the male rock climber at the start and one of the soldiers before he was cast as Mister Terrific and Black Manta expy Devil Ray in the final season.
- In the first season of DuckTales (1987), Hamilton Camp voiced a few minor characters before voicing Gizmoduck in season two.
- In season 1 of Elena of Avalor, Grey DeLisle Griffin voices Dr. Mendoza. In late season 2, she's cast as Ash Delgado, who takes over as the main villain.
- The Loud House:
- Lincoln's first regular voice actor, Grant Palmer, would later voice Grant, an employee at the Burping Burger, after he hit puberty.
- Tex Hammond, son of series regular Grey Griffin, initially voiced minor character Lance before becoming Lincoln's third regular voice actor. Hammond's successor, Asher Bishop, also initially voiced Simon Sharp before getting cast as Lincoln.
- In Rugrats, Tara Strong voiced Timmy McNulty, a Jerkass neighbor of the babies around Angelica's age, before going on to voice Tommy's brother Dil.
- On Scooby-Doo! Mystery Incorporated:
- Kate Higgins voiced some minor characters in Season 1 (namely Principal Quinlan in one episode) before being cast as Mayor Janet Nettles in Season 2.
- Tia Carrere played Amy in "The Siren's Song" before being cast as adult Judy in Season 2.
- The Simpsons: In the Canadian French dub, Alain Zouvi voiced several one-shot characters such as Brad Goodman, Hank Scorpio, and Frank Grimes. Afterward, ever since "Lisa the Skeptic", he became the official voice actor for both Smithers and Apu, replacing the late Jean-Louis Millette in both roles.
- In Sofia the First, Megan Hilty played Princess Charlotte in season 3's "Beauty Is The Beast" before being cast as Prisma, the main antagonist in the Mystic Isles story arc for season 4. Likewise, Andrew Rannells, who voiced Morris in that episode, would voice Skye, Sofia's flying horse companion in the titular isles, another regular in season 4. There's also Fiona Bishop, who voiced Ruby in the pilot movie "Once Upon A Princess", voicing Princess Zooey, and Buttercup twins Meg and Peg.
- Spongebob Squarepants: In the Spanish dub, Luis Miguel Perez did additional voices and dubbed the songs, "Doing the Sponge" and "Loop De Loop", before replacing Oscar Zuloaga as Plankton.
- Star Wars Resistance:
- Josh Brener, a friend of Rebels main cast member Tiya Sircar (Sabine), was the voice of Senator Mon Mothma's attaché, Erskin Semaj, before later playing a main role as Neeku Vozo.
- Gary Anthony Williams played One-Shot Character Separatist General Riff Tamson on The Clone Wars before later playing recurring character Kragan Gorr.
- In the Latin American dub of Steven Universe, Valentina Toro voiced Alexandrite in her first appearance before later going on to voice Jasper. Ironically, her sister Antonia would voice Alexandrite in her second appearance. Similarly, before she became the Spanish voice actress for Ruby, Judith Noguera voiced minor (as in, she doesn't even have her own voice actress in the original language) recurring character Jane.