The intersection of Suspiciously Similar Substitute and Second Episode Introduction. This trope is when a character featured in the pilot episode (and clearly meant to be a main player in the series) is missing from the second episode, replaced by a similar character for the rest of the series' run. Note that this is not a case of The Other Darrin occurring between the first and second episodes, the substitute is explicitly a different character.
This often happens because pilots are produced well before the full series is picked up; episode two is prime time for characters to get dropped, recast, or replaced... sometimes even big chunks of the premise and/or tone don't make it to the regular series.
Contrast Decoy Protagonist.
- The two One Piece pilots each had early prototypes of the character that would become Nami when the series got picked up. The first pilot had Silk, an orphan who tries to rally her village to defend themselves against the pirates pillaging the village. The second pilot had Ann, a girl who was trying to rescue her best friend, a bird, from pirates.
- In the second One Piece pilot, Luffy received his straw hat and dream of being a pirate from his grandfather. When the series got picked up, Luffy received both of these things from Shanks.
- The pilot of Seinfeld has Jerry and George interact with Claire, the Deadpan Snarker waitress at Pete's Luncheonette, originally meant to be the female role of the series. In the second episode, "The Stake Out", Claire is gone, the diner is Monk's Cafe, and the female role is Jerry's ex-girlfriend, Elaine (though she appears at the end of "Male Unbonding", the second episode produced, to help Jerry come up with ideas to avoid a childhood friend). NBC felt the show was too "male-centric" and demanded that there be a female role (although if Claire was meant to be the female role, one might wonder why she was dropped in the first place).
- Lee Garlington, who played Claire, was apparently let go because of her criticisms of Larry David's writing.
- The Pilot of New Girl had Coach as the third roommate to Nick and Schmidt. However his actor Damon Wayans Jr. was already committed to another TV show on a different network, ABC's Happy Endings, so the second episode of New Girl had him replaced with Winston. After Happy Endings was cancelled, Wayans returned to the show as Coach in Season 4...and promptly left again at the end of the season.
- Hogan's Heroes featured a Russian POW named Vladmir in its pilot episode, though when the series was picked up, actor Leonid Kinsky refused to renew his contract, as he disliked how lightly the Nazis were portrayed; so saying, Larry Hovis as Carter was promoted to full-time regular, after initially appearing as a one-shot guest character in the pilot.
- In the pilot of Eureka, the head of Global Dynamics was a character named Warren King. He was replaced by Nathan Stark (offscreen) starting in the second episode.
- Star Trek: The Original Series is a complicated case, as it had two pilot episodes ("The Cage" and "Where No Man Has Gone Before"), and though they both formed part of the series' first season, neither was the first episode aired.
- If "Where No Man Has Gone Before", the successful pilot, had aired as the first episode, the replacement of Dr. Mark Piper with the younger but otherwise very similar Dr. Leonard McCoy would be a straightforward example of this trope. (The wholesale replacement of the regular cast, except Spock, between the first, unsuccessful, pilot, and the second, successful, pilot is probably a different trope.)
- Dr. McCoy is an interesting example in that he is basically this trope in reverse: Gene Roddenberry always wanted DeForest Kelley for the Doctor, all the way back to the first pilot, but was overruled by each pilot's director (Robert Butler favoured John Hoyt as Dr. Boyce, and James Goldstone preferred Paul Fix as Dr. Piper). Only when the show went to series could Roddenberry cast Kelley without interference.
- A straighter example of this trope is the Captain's Yeoman: Colt in "The Cage" (played by Laurel Goodwin) was replaced by Smith (played by Andrea Dromm) in "Where No Man Has Gone Before". Dromm declined to continue with the series to pursue a film career, and so was replaced by Grace Lee Whitney as Yeoman Rand for "The Corbomite Maneuver" (which also introduced Bones and Uhura).
- Communications Officer Alden in "Where No Man Has Gone Before" is replaced by Lieutenant Uhura in the series.
- Between first pilot "The Cage" and second pilot "Where No Man Has Gone Before", Captain Pike was replaced with Captain Kirk. The episode also introduces Scotty (who seems to replace the minor character Pittrodie) and Sulu (who, in terms of dynamic if not function aboard the ship, basically replaces Tyler).
- The pilot movie that launched Babylon 5 was aired separately months before the series itself began, which led to cast complications and several substitutions in the first regular episode:
- The First Officer, Laurel Takashima, was replaced by Susan Ivanova.
- The chief surgeon, Doctor Kyle, was replaced by Doctor Franklin (although technically that was a third episode substitute; neither of them appears in the episode after the pilot).
- The Resident Telepath, Lyta Alexander, was replaced by Talia Winters (who was later written out and replaced with Lyta Alexander).
- At least two of these replacements (possibly not Takashima) became plot points.
- In Space: 1999, black computer expert Ben Ouma is replaced by black computer expert David Kano after the first episode.
- In The Sarah Jane Adventures Kelsey, a female school chum character in the first episode is replaced by Clyde, a male school chum character in the second.
- It helps that both are Black, snarky, initially obnoxious and the Secret Keeper.
- In the original CSI the Audience Surrogate character Holly Gribbs was quickly replaced with the eerily similar Sara Sidle because she was generally hated by test audiences... the creators had anticipated as much. As a result, they decided for Holly to die (rather than recover) in the second episode.
- Night Court changed defense attorneys several times, but the first time was between the pilot and second episode where Gail Strickland as Sheila Garnder was replaced with Paula Kelly as Liz Williams.
- The JAG Pilot Movie had Caitlin Pike as Harm's partner on the USS Seahawk investigation. In the series proper she was replaced by Meg Austin.
- The two JAG episodes that act as the pilot for NCIS had a character named Vivian Blackadder on Gibbs' team. She was dropped for the series proper, so the first real episode introduced Caitlin Todd as a secret service agent who transferred to NCIS for episode 2.
- It happened again for NCIS: Los Angeles - Special Agent Macey was introduced as the head of the LA branch in the two-parter pilot on NCIS. Come the series proper, Macey's been replaced by Hetty. In addition, they've moved to a new building.
- Juliet O'Hara was introduced in the second episode of Psych, replacing Lassiter's partner from the pilot after she was transferred due to a ban on inter-office affairs.
- In the pilot of Elementary Captain Gregson has a Hispanic partner named Detective Javier Abreu who was skeptical of Holmes' deductive skills and questioned the necessity for his consultation. From the second episode on, Captain Gregson has an African American partner named Detective Marcus Bell who is skeptical of Holmes' deductive skills and questions the necessity for his consultation.
- Sirens (US) Theresa's new partner in the pilot gets transferred pretty quickly and is replaced with Billy in episode two.
- NewsRadio featured an oddball maintenance man character named Rick(played by Greg Lee best known for Wherein The Worldis Carmen Sandiego) who gets replaced in the second episode with the younger and hunkier Joe Rogan.
- In the pilot for The Wizard, the caretaker is a woman named Darcy Stafford, played by Gates McFadden. Episode 2 explains that Darcy got transferred to a different assignment, and her caretaker job eventually goes to Tillie Russell, played by Fran Ryan.
- Constantine, after Liv Aberdine was written out after the pilot, the second episode brings Zed Martin who also has psychic abilities. She also has a cameo at the end of the reshoot pilot.
- The Simpsons: A rare In-Universe example (of sorts) occurs on an episode ("Homer To The Max"), where a Show Within a Show called "Police Cops" has a character called Homer Simpson, which gives Homer some fame within the town. The episode right after the pilot keeps the Homer character in name only, changing him from an apparent Expy of "Sonny" Crockett into an utterly incompetent Chris Farley-esque idiot. The ridicule of people afterwards is so bad that Homer decides to change his name to "Max Power".
- Steven Universe has another In-Universe example: in the pilot of Li'l Butler, the family had a cat named Money, which was apparently replaced by a dog in the next episode.