"Theatricality" is the twentieth episode of the American television series Glee. The episode was written and directed by series creator Ryan Murphy, and premiered on the Fox network on May 25, 2010.

In "Theatricality", glee club member Tina Cohen-Chang (Jenna Ushkowitz) has an identity crisis. The female club members and Kurt (Chris Colfer) pay tribute to Lady Gaga, performing in a selection of her costumes, while the rest of the male club members perform as Kiss. Rachel (Lea Michele) meets her mother Shelby (Idina Menzel), the coach of rival glee club Vocal Adrenaline, and Finn (Cory Monteith) and his mother move in with Kurt and his father, leading to a confrontation between Kurt and Finn, and Finn continuing to control Kurt about keeping his sexuality away from him, and using scare tactics to keep Kurt away. The episode features cover versions of five songs, all of which were released as singles, available for digital download, and three of which are included on the soundtrack album Glee: The Music, Volume 3 Showstoppers.

"Theatricality" was watched by 11.5 million American viewers and received generally positive reviews from critics. Tim Stack of Entertainment Weekly deemed it one of his favorite episodes of the season, and both Terri Schwartz of MTV and CNN's Lisa Respers France compared it positively to the Madonna tribute episode, "The Power of Madonna". O'Malley's acting and the Kurt and Finn storyline attracted critical praise, although Jarett Wieselman of the New York Post felt that similar scenes between Kurt and Burt were becoming increasingly frequent, diminishing their impact. BuddyTV's Henrik Batallones and Mary Hanrahan of Broadway World highlighted pacing issues with the Rachel storyline, and Hanrahan and Kevin Coll of Fused Film criticized the use of "Poker Face" as a mother–daughter duet.

Principal Figgins (Iqbal Theba) informs Tina (Jenna Ushkowitz) that she can no longer dress as a goth, alarmed by a spate of pseudo-vampirism in the school, inspired by the Twilight series. She briefly changes her style, before dressing as a vampire and convincing Figgins that if he does not allow her to wear her preferred clothes, her vicious Asian vampire father will bite him.

Rachel (Lea Michele) discovers that rival glee club Vocal Adrenaline is planning on performing a Lady Gaga number at Regionals, so glee club director Will Schuester (Matthew Morrison) sets the club a Gaga assignment. The girls and Kurt (Chris Colfer) create costumes inspired by Lady Gaga and perform "Bad Romance". The rest of the male club members, unwilling to do a Gaga number, dress as Kiss and perform "Shout It Out Loud". Puck (Mark Salling) suggests to Quinn (Dianna Agron) that they name their daughter Jackie Daniels, as in Jack Daniel's. Later, in an attempt to show her he is serious about being a father, he does another Kiss song with the guys, "Beth", and suggests that Quinn give that name to their daughter. Quinn agrees that he can be present at her birth.

While spying on a Vocal Adrenaline rehearsal, Rachel shockingly realizes that their director, Shelby Corcoran (Idina Menzel), is her biological mother. She introduces herself, and Shelby makes her a better Lady Gaga costume. Will meets with Shelby, concerned that she is not as invested in forging a relationship as Rachel is. Shelby confesses that she can no longer have children, but wishes she could have her baby back, rather than the now fully grown Rachel, whom she feels does not need her. She tells Rachel that instead of trying to act like mother and daughter, they should just be grateful that they have met, and maintain their distance. Rachel hugs her goodbye, and they duet on an acoustic version of "Poker Face".

Kurt's father Burt Hummel (Mike O'Malley) invites Finn (Cory Monteith) and his mother Carole Hudson (Romy Rosemont) to move in with them. Finn feels awkward sharing a room with Kurt, who had a small crush on him. Kurt wants to show interest and asks Finn about his decorations in the basement. Finn continues bullying Kurt about his sexuality, and during an argument insults several items in his bedroom as being "faggy" after losing his temper. Burt overhears this and punishes Finn for bullying Kurt by using that term by dismissing him from the house, even if it costs Burt his relationship with Carole. Finn tries to apologize to Kurt, but he refuses to accept his apology. Kurt is bullied for his Gaga costume by football players Dave Karofsky (Max Adler) and Azimio (James Earl). Finn creates his own costume out of a shower curtain, and tells them he will not let them hurt Kurt, backed by the rest of the glee club. Meanwhile, at the end of the episode, while Figgins walks out of the office, he has an illusion that Tina is really a vampire, and threatens to kill him if he doesn't let her wear her usual clothing.

"Theatricality" was originally intended to air on June 1, 2010, but was switched in the schedule with the episode "Funk". The impetus for the Lady Gaga tribute comes from Tina's conflict, with Ushkowitz explaining that the storyline reflects Tina "slowly coming out of her box. Making her way out of her shell." As well as allowing Glee the rights to her songs, Lady Gaga also loaned the series her costume designer to recreate her signature looks. Series creator Ryan Murphy, who also directed the episode, stated that, because of the elaborate staging and costuming, the performance of "Bad Romance" was the show's most expensive number to date. "Bad Romance" took six hours to film, with Murphy describing it as "big and athletic and hard." Michele damaged her knee from exertion during the performance. In a statement released to Entertainment Weekly, Gaga eagerly anticipated the covers of her songs: "I love Glee. I love the cast and the creativity of the writers. I went to a musical theatre school, and used to dream that someday the students would be singing my songs. Can’t wait for "Bad Romance" + "Poker Face" in Glee fashion!"