[[folder:Characters Introduced in Season 1]]
!Julia Houston (Creator/DebraMessing)
Book writer and lyricist of the creative team, Julia is a talented and successful writer whose personal and professional lives often clash, sometimes with disastrous results.

* BigSisterInstinct: In the surrogate family that is the ''Bombshell'' team, Julia tends to act as the protective big sister. She and Tom, in particular, tend to toggle back and forth over who is the reassuring older sibling and who is the mess of a younger sibling at the moment.
* DeadpanSnarker: Julia, following [[spoiler: the rehearsal in which everyone finds out that Rebecca Duvall can't sing.]]
--> '''Eileen:''' What we need is a constructive solution!
--> ''beat''
--> '''Julia:''' Group suicide?
* FieryRedhead
* LoveHurts: Falling for Michael leads to nothing but trouble for her family life and even bleeds into her professional life, due to their working relationship.
* LoveTriangle: With Frank and Michael Swift. [[spoiler: The finale implies she and Michael get back together]].
* MostWritersAreWriters: Julia (like series creater Theresa Rebeck) is a playwright.
* OneHourWorkWeek: Averted; Julia and the rest of the team spend a realistically large proportion of time either at rehearsals or working on the musical.
* PlatonicLifePartners: With Tom.
* ScarfOfAsskicking: Not so much. Julia's perpetual choice of unflattering scarves is even lampshaded during Season 2.
* StarvingArtist: Averted; we meet Julia at the point in her career where she is already a successful writer.
* TearsOfFear: When her son, Leo, runs away from home.
* YourCheatingHeart: Twice, with actor Michael Swift.

!Derek Wills (Jack Davenport)
[[caption-width-right:300:"No matter what happens next don't ever doubt you are a star."]]
The no-holds-barred director and choreographer with brilliant visions but a serious disregard for others. Has a nasty past with Tom and puts his work above all else.

* TheAlcoholic: Often turns to drinking when having problems. All he does for several days just before the Tony awards is sleep and drink.
* BadassLongcoat: Derek has quite a few. They resemble like those of another [[Series/DoctorWho famous Brit.]]
* CastingCouch: Sleeps with two of his three Marilyns, and comes ''thisclose'' to the third, as well as several others (which eventually comes back to bite him in a ''big'' way). He genuinely does fall in love with Ivy, though.
* DeadpanSnarker: Has a dry comeback for every occasion, particularly directed at Tom and/or Jimmy:
-->'''Jimmy''': Lea Michele? ''Lea Michele?''
-->'''Derek''': If you say it one more time, she magically appears!
* HandsomeLech: More than happy to use his rakish good looks to bed a pretty chorus girl or leading lady.
* InsufferableGenius: Derek is an in-demand director and choreographer and ''knows'' it.
* {{Jerkass}}: Derek appears to have a reputation for being talented, but a massive jerk:
** JerkWithAHeartOfGold: YMMV, but Derek's "jerk" behavior is just managing show business. When he's speaking to Ivy as a human being (as opposed to a director), he's fairly tenderhearted and supportive. He's not a bad or uncaring person. He drives people hard (and/or manipulates them) to create the best art he can.
* LoveConfession: Acknowledges his love for Ivy at no smaller event than the Tonys.
* LoveTriangle: Attracted to both Ivy and Karen, but ends up in a full-blown romantic relationship with Ivy while settling into a friendlier muse-director relationship with Karen.
* MeanBrit: A harsh perfectionist to the point of outright cruelty towards his cast, and sometimes even his fellow creative team members.
* OnlySaneMan: Tends to think he is, given he is less emotional than his colleagues, but is a bit of a mad genius in his own way.
* Nepotism: Accepts the idea that a critic once praised him because said critic was a longtime family friend. Tom reveals that in fact the critic was sleeping with Derek's father.
* PermaStubble: Generally well-kept, but grows into a full-on BeardOfSorrow during his pre-Tonys disaster.

!Karen Cartwright (Katherine [=McPhee=])
An aspiring actress from the Midwest with little in the way of experience but a powerful voice that gains immediate attention.

* AudienceSurrogate: A fairly generic, nice character who serves as the audience's window into the theater world.
* CountryMouse: The more experienced cast members tease her about being this, although technically she's more like a "Midwest suburban mouse".
* TheIngenue: Sweet, naive, inexperienced, yet talented.
* InSeriesNickname: Her castmates call her "Iowa," at first as a derogatory shot at her inexperience and Midwestern upbringing, later as an AffectionateNickname.
* TheMuse: Karen claims to be this for Derek in the Season 2 series premiere, following several scenes in Season 1 in which he hallucinates her as Marilyn.
* NaiveNewcomer: A Midwesterner with essentially no showbiz experience, she finds herself in ''way'' over her head and has no idea how to navigate the professional and sexual politics of the theater world.

!Tom Levitt (Christian Borle)
Composer and writing partner to Julia, Tom brings stability and wit, despite his own occasional temper and failed personal life.

* BerserkButton: Don't call Tom's music "boring".
* DeadpanSnarker: Probably the snarkiest character aside from Derek.
-->'''Tom''': Art without torture. I don't think it's possible.
* NiceGuy: Has his diva moments like the rest of the cast, but generally tries to treat everyone kindly and respectfully (except [[BerserkButton Derek]]).
* PlatonicLifePartners: With Julia.

!Ivy Lynn (Megan Hilty)
A longtime chorus girl and Broadway vet, Ivy is a triple threat who may have finally gotten her big break.

* AmbitionIsEvil: Initially presented as an antagonist for the simple fact that her ambitious career goals put her opposite Karen.
* AlphaBitch: Ivy behaves like this towards Karen by being rude to her or passive aggressively trying to get her thrown out of the workshop. She gets a little better.
* BlondesAreEvil: The show quite obviously pushes Karen as 'good' and Ivy as 'bad.'
** She's an AntiVillain or VillainyFreeVillain, only by being protagonist Karen's competitor for the role of Marilyn. But it's WhiteAndGrayMorality, in that Ivy is shown as less deserving (as a person) than Karen, but not truly 'bad'.
* DependingOnTheWriter: Gets hit with this ''hard'' in Season 1. Depending on the episode, Ivy is portrayed as either a pathetic victim, a vengeful diva, or a genuinely hard-working actress. Season 2, fortunately, evens her out.
* Deuteragonist: Karen is the point-of-view character, but the story is driven almost equally by Ivy's arcs.
* InadequateInheritor: Struggles with feeling unworthy to follow in the footsteps of her famous, acclaimed mother.
* MamasBabyPapasMaybe: Invoked and subverted. When [[spoiler: Ivy becomes pregnant]], Sam asks if [[spoiler: the father could be anyone but Derek]]. She immediately answers in the negative.
* MommyIssues: Her mother was (and still is) a huge Broadway star who enjoys the spotlight and can often be insensitive, leaving Ivy with no small amount of confidence issues.

!Eileen Rand (Creator/AnjelicaHuston)
The producer of ''Bombshell'', Eileen is passionate about the material but also trying to pull herself up professionally and personally following the nasty implosion of her marriage to her producing partner.

* BenevolentBoss: Despite being technically in charge and very no-nonsense, Eileen treats her co-workers and employees with respect.
* DeadpanSnarker: Along with the rest of the ''Bombshell'' team, has a very dry sense of humor.
* OnlySaneMan: As the non-creative partner, tends to be the most levelheaded and business-minded
* TeamMom: Spends a fair amount of time wrangling the rest of the creative team and trying to work out their differences.

!Sam Strickland (Leslie Odom Jr.)

* BlackBestFriend: To Ivy
* StraightGay: He doesn't want to have to wear a label, but his massive love for sports and lack of any stereotypical gay mannerisms make Michael Swift comment that, if he wants to get a date with anybody, he might literally have to.
* TwoferTokenMinority: Subverted, as he's both gay and black but he's also a big sports fan and a regular churchgoer, two traits not often found among actors/dancers. The actor who plays him downplays his sexuality in interviews, saying it shouldn't matter.

!Ellis Boyd

* ItsAllAboutMe: He honestly believes that his comment on Marilyn is what created the musical, everyone owes jobs to him and that he's key to the show. When he snaps to Eileen on his supposed skills and he should be named a producer, she fires him.
* JerkAss: Ellis, what with his constant squabbling with Julia and [[spoiler: poisoning Rebecca Duval in an attempt to put Ivy in the role of Marilyn]].
* ProfessionalButtKisser: Towards Tom, Derek, and Eileen.
* PutOnABus: Following extremely negative fan reaction, was fired at the end of Season 1 and completely written out for Season 2.
* TheScrappy: Ellis, for Julia in-universe (And for many fans as well)

!Dev Sundaram

* TheObstructiveLoveInterest: Professes support for Karen's career but tends to hinder her more often than not.

!Frank Houston (Brian D'arcy James)

* NiceGuy: All-around decent, kind, supportive husband to Julia, despite his misgivings- until he finds out [[spoiler: about her affair]]

!Michael Swift (Will Chase)

* TheOneThatGotAway: Seems to view [[spoiler: Julia]] as this, and the feeling is mutual.
* TenorBoy: Both InUniverse and for the show, though with considerably more moral ambiguities.
* YourCheatingHeart: Cheats on his wife [[spoiler: with Julia]]

!John Goodwin (Neal Bledsoe)

* HelloAttorney: Tom is unenthusiastic about going out with the lawyer his mother set him up when. Once he sees him? "Yay, Mom."
* SatelliteLoveInterest: John hangs around for a few episodes, helps Leo out with his legal issues, and gets dragged along to a few events before dumping Tom over his obvious attraction to Sam. That's about it.

!Leigh Conroy (Bernadette Peters)
* ParentalNeglect: Though not intentionally cruel, her ambition, sharpness, and lack of filter made her a less-than-ideal mother to an insecure young Ivy.
* RealLifeRelative: InUniverse, as the ''Bombshell'' team brings on Leigh to play Marilyn's mother, playing on the publicity of having a real mother and daughter playing Gladys and Marilyn.
* StageMom: Literally, too.

!Rebecca Duvall (Uma Thurman)


[[folder:Characters Introduced in Season 2]]
!Jimmy Collins (Jeremy Jordan)
* {{Jerkass}}
* TheStoner

!Kyle Bishop (Andy Mientus)
* Adorkable: Particularly in his awkward early attempts at flirting and whenever he meets someone famous.
* AscendedFanboy: Has loved the theater his whole life and now finds himself right in the middle of it all.
* TheKnightsWhoSaySquee: Even once ''Hit List'' becomes a realized production, he consistently fanboys over his theatrical idols.
* MoralityPet: Does all he can to keep Jimmy in line.
* YourCheatingHeart: [[spoiler: With his celebrity crush, Tom Levitt.]]

!Ana Vargas (Krysta Rodriguez)
* AlwaysSomeoneBetter: Often feels overshadowed, particularly by Karen.

!Scott Nichols (Jesse L. Martin)

!Blake (Daniel Abeles)

* SatelliteLoveInterest: All we ever really know about him is that he's a lighting designer, he can stand up to Derek, and he really likes Kyle.

!Patrick Dillon (Luke Macfarlane)

* TransparentCloset: Apparently ''everyone'' knows he's gay, even though he insists otherwise. Eileen even comments that he's the reason they invented the term "glass closet."