In 1959, following the flop of the theatrical musical Funny Boy (based on William Shakespeare's Hamlet) ("Opening Night"), the show's washed-up producer, Max Bialystock, hires the neurotic Leo Bloom as his accountant. While studying Max's books, Leo notes that as a flop is expected to lose money, the IRS will not investigate the finances of failed productions. Leo jests that by selling an excess of shares and embezzling the funds, a flop could generate up to $2 million. Max asks for Leo's help with the scheme, only for the latter to refuse ("We Can Do It").
Returning to his old accounting firm, Leo starts fantasizing about being a Broadway producer ("I Wanna Be a Producer"). Leo quits his job and forms "Bialystock & Bloom" with Max. Searching for the worst play ever written, the duo finds Springtime for Hitler, a musical written by an ex-Nazi named Franz Liebkind. Max and Leo, in order to acquire Franz's rights to the musical, perform Hitler's favorite song and swear the sacred "Siegfried Oath" to him ("Der Guten Tag Hop-Clop").
In order to ensure the play's failure, Max and Leo meet failing, flamboyant director Roger De Bris and his assistant Carmen Ghia. Roger is reluctant to direct, but when Max and Leo suggest he could win a Tony Award, he agrees on the condition that the play be more "gay" ("Keep It Gay"). Back at their office, a Swedish woman named Ulla appears to audition. Although Leo points out that they have not started casting, Max hires her as their secretary until they audition her later ("When You've Got It, Flaunt It").
To gain backers to fund the musical, Max has dalliances with several elderly women ("Along Came Bialy"), allowing him to raise the $2 million. Leo laments about the dangers of sex distracting him from his work, and shares a kiss with Ulla ("That Face"). At auditions for the role of Hitler, Franz, angered at a performer's rendition of a German song, storms the stage and performs it himself ("Haben Sie gehört das Deutsche Band?"). Based on the performance, Max hires Franz to play Hitler.
On opening night, as the cast and crew prepare to go on stage, Leo wishes everyone good luck, to which everyone warns it is bad luck to say "good luck" on opening night, and that the correct phrase is to say "break a leg" ("You Never Say Good Luck on Opening Night"). Franz leaves to prepare and literally breaks his leg in a fall. Max enlists Roger to perform the role in his place, and Roger accepts.
As the show opens, the audience is horrified at the first song ("Springtime for Hitler"), and people begin leaving out of disgust until Roger enters as Hitler ("Heil Myself"). Roger, playing Hitler very flamboyantly, causes the audience to misinterpret the play as satire, resulting in the show becoming a smash. Terrified the IRS will learn of their crimes, a dispute breaks out between Max and Leo, but stops when Roger and Carmen come into the office to congratulate them. Furious at Roger for making the play successful, Max angrily confronts Roger for his actions, and even goes as far to physically torture Carmen when he tries to defend Roger. Franz then appears and attempts to shoot all four of them for breaking the Siegfried Oath by mocking Hitler, only to attract the police. As Max and Franz attempt to evade the police, Franz breaks his other leg.
Arrested for his tax fraud, Max is imprisoned while Leo elopes with Ulla to Rio de Janeiro ("Betrayed"). About to be sentenced, Max is saved by Leo, who returns to defend him ("'Til Him"). The judge, realizing Max and Leo are inseparable, sentences them both to five years at Sing Sing Prison with Franz. Writing and producing a new musical in prison ("Prisoners of Love"), Leo, Max, and Franz are pardoned by the governor for their work, allowing them to collaborate with Roger and Ulla and release Prisoners of Love. The play's success means Max and Leo go on to become successful Broadway producers.
In a post-credits scene, the cast sings "Goodbye!", telling the audience to leave the theater.
Nathan Lane as Max Bialystock
Matthew Broderick as Leopold "Leo" Bloom
Uma Thurman as Ulla Inga Hansen Benson Yansen Tallen Hallen Svaden Swanson (later Bloom)
Will Ferrell as Franz Liebkind
Gary Beach as Roger De Bris
Roger Bart as Carmen Ghia
Jon Lovitz as Mr. Marks
Michael McKean as Prison Trustee
David Huddleston as Judge
Richard Kind as Jury Foreman
Eileen Essell as Hold Me-Touch Me
Debra Monk as Lick Me-Bite Me
Andrea Martin as Kiss Me-Feel Me
John Barrowman as the Lead Tenor Stormtrooper
Brent Barrett as Brian
Peter Bartlett as Kevin
Jim Borstelmann as Scott, Donald Dinsmore
Kathy Fitzgerald as Shirley Markowitz
Ronald Rusinek as Jack Lepidus
Jason Antoon as Jason Green
Bryn Dowling and Meg Gillentine as Usherettes
Marilyn Sokol as Bag Lady
Danny Mastrogiorgio as Jail Guard
Mel Brooks as himself, voices of Tom the Cat, Hilda the Pigeon and German Soldier
Fran Brill - Pigeon
Tyler Bunch - Pigeon
James Kroupa - Pigeon
Tim Lagasse - Pigeon
Peter Linz - Pigeon
Drew Massey - Pigeon
Joey Mazzarino - Pigeon
Martin P. Robinson - Pigeon
Matt Vogel - Pigeon
Victor Yerrid - Tom the Cat, Hilda the Pigeon, Adolf the Pigeon
based on the eponymous 2001 Broadway musical, which in turn was based on Brooks's 1967 film of the same name