Riggan Thomson, portrayed by Michael Keaton, is a once-famous actor best known for his role as the superhero Birdman in a beloved trilogy spanning from 1989 to 1992. Haunted by the sardonic and critical voice of his former self, Riggan is tormented by visions of superhuman abilities, constantly grappling with the possibility that he might still be, in some sense, Birdman himself.
In an effort to reclaim his former glory, Riggan embarks on an ambitious project, writing, directing, and starring in a Broadway adaptation of Raymond Carver's poignant short story, What We Talk About When We Talk About Love. However, the insistent voice of Birdman seeks to pull him back into the realm of blockbuster films, insisting that Riggan’s identity is intertwined with the character. The voice taunts him, suggesting that actors like Robert Downey Jr., who may lack true talent, are thriving due to their involvement in the Marvel universe.
The media paints Riggan as a washed-up star who turned down a lucrative role in Birdman 4 twenty years prior, adding to his desperation. His close friend and attorney, Jake, is devotedly supporting the play, which also features Riggan's girlfriend, Laura, and rising Broadway talent Lesley. Riggan's daughter, Sam—a recovering substance abuser he struggles to connect with—assists him on this tumultuous journey.
The day before their highly anticipated first preview, disaster strikes when a stage light falls on Riggan's co-star, Ralph. Riggan confides in Jake, admitting he unintentionally caused the incident using his supposed superpowers. Faced with the prospect of financial ruin and with the press waiting to pounce, they decide against canceling the preview.
In a desperate move, Riggan agrees to replace Ralph with the volatile but talented method actor Mike Shiner, who is also Lesley’s boyfriend. Mike's energetic approach to acting excites Riggan, despite concerns about his costly influence on the production. Riggan, engaged in an affair with Laura, pushes forward, believing that Mike's presence will save the play.
However, the first previews unravel spectacularly. Mike's behavior results in chaos on stage, including a tantrum mid-performance and inappropriate actions directed toward Lesley. Riggan’s insistence on keeping Mike for ticket sales leads to mounting tension, forcing Riggan to weigh the financial implications against the artistic vision he holds dear.
In a heartfelt exchange with his ex-wife Sylvia, Riggan contemplates mortgaging his house, revealing the depths of his commitment to the play. As frustrations mount, Riggan copes with turbulent interactions, especially after a confrontation with Sam about his relevance in the modern world.
The final preview is fraught with anxiety when Riggan finds himself locked out of the theater in nothing but his underwear, inadvertently becoming a viral sensation on social media. While he embarks on an unexpected journey of self-exploration, Tabitha Dickinson, a sharp-tongued critic, threatens to annihilate the play before it even begins.
Despite the chaos, opening night dawns, and Riggan finds solace in the performance's success, sharing a moment of vulnerability with Sylvia. However, in a shocking climax, Riggan enacts his character's heartbreaking end by shooting himself on stage—his misfortunate act creating a standing ovation from the audience, mistakenly perceived as part of the performance.
Waking up in a hospital, Riggan learns that his suicide attempt has inadvertently brought positive reviews, as Tabitha misinterprets the event as a bold new acting technique. Sam visits with flowers, capturing the moment to bolster his online presence.
While Sam briefly leaves the room to find a vase, Riggan confronts his identity and future. He unravels the bandages revealing his reconstructed nose, bids farewell to Birdman, and in a moment of reckless abandon, climbs out the window to embrace the freedom he longs for. As Sam returns to find the room empty, a smile graces her face while she gazes up at the soaring birds above.
