- Awesome, Dear Boy: Johnny Depp was sold on the idea of doing a musical about a serial killer.
- Breakaway Pop Hit: "Not While I'm Around" is written in a more pop-influenced style than the rest of the show, and managed to spin off a couple of pop recordings.
- The Cast Showoff: Beadle Bamford is usually expected to actually play the harmonium. This actually became the novelty of the 2005 revival, where the cast was reduced to only the ten players who doubled as both the stagehands and the orchestra, each playing their own instrument.
- Creator-Preferred Adaptation: In his book Finishing the Hat, Stephen Sondheim states the 2007 film is the only adaptation of one of his works for the screen that he approves of.
- Cut Song:
- The Judge's 'Johanna' was cut from the original production because it held up the plot (and is incredibly creepy) but appears on the original cast album and was eventually reinstated. The tooth pulling part of the Contest is also often cut, and "Parlour Songs" is sometimes heavily abbreviated.
- Several songs from the Broadway musical were excised from the film: "The Ballad of Sweeney Todd" (and its many reprises), "Ah, Miss," "Johanna" (Judge Turpin's version), "Kiss Me," "Parlour Songs," "City on Fire," and "Epilogue." All ensemble/choral singing was also eliminated, most notably from "God, That's Good," in which the title of the song is now never even sung. Many other songs remaining in the film have been shortened. The only songs to remain intact are "Epiphany," "Pretty Women," "Johanna" (Anthony's solo), "The Worst Pies in London," "Wait" and "My Friends." "Johanna" (featuring Sweeney, Anthony, and the Beggar Woman) is originally a quartet featuring all three in addition to Johanna's vocals. The song "My Friends" is not sung in its entirety either, with one line being added and the last line was edited, from "At last, my right arm is complete again" to "At last, my arm is complete again."
- Dawson Casting: A lesser example - Jayne Wisener was 19 when she played the 15 year old Johanna.
- Hide Your Pregnancy: Helena Bonham-Carter was pregnant during the film production, resulting in magical size-changing breasts over the course of the movie.
- Non-Singing Voice: Averted. Every single actor in the film version does their own singing, despite several of them never singing in a production before. It doesn't show, either. Helena Bonham-Carter was required to do a vocal audition for the role - to her own husband, per Sondheim's request.
- Orphaned Reference: Most productions cut out the tooth-pulling part of The Contest, but neglect to write out Pirelli's singing "To shave-a the face/to pull-a the 'toot'." The movie, which also cuts the tooth-pulling, adjusts the lyrics accordingly.
- Promoted Fanboy: Tim Burton saw the original West End production just as his show business career was starting, and had Stephen Sondheim's blessing as early as the mid-80s to make the movie version.
- Saved from Development Hell: This film had been in development for over twenty-five years. At that point in time, hundreds of actors were either considered or attached to the project, to play Sweeney Todd: Warren Beatty, Tim Curry, Robert de Niro, Michael Douglas, Richard Dreyfuss, Harrison Ford, Gene Hackman, Dustin Hoffman, William Hurt, Kevin Kline, Steve Martin, Jack Nicholson, Al Pacino, Robert Redford and many more.
- What Could Have Been:
- The original script initially kept the opening and the reprising ballad intact with a chorus of ghosts singing. Christopher Lee and Anthony Head were amongst those to play the ghosts. However Johnny Depp's daughter fell ill during shooting, so he took time off to be with her, which caused the shooting schedule to become tight, and the ghosts had to be axed. There is a YouTube video of Lee recording his song out there somewhere.
- While one probably has nothing to do with the other, Tim Burton had always anticipated cutting the ballad, as well as other songs, to make the film feel less like a filmed stage show and more like a movie.
- Annette Bening, Toni Collette, Nicole Kidman, Cyndi Lauper, Bernadette Peters, Imelda Staunton, Meryl Streep, Emma Thompson and Kate Winslet were all considered for Mrs. Lovett.
- Anne Hathaway was almost cast as Johanna, but Burton wanted a complete unknown actress for the role and settled with Jayne Wisener.
- Sam Mendes was originally attached to direct with Russell Crowe in the title role.
- Kevin Smith when working for Warner Bros. on Superman Lives was interested to direct the film when told the studios had the rights. But then admitted he was more interested in seeing Burton's version when told they were hoping for Burton to direct.
Trivia / Sweeney Todd: The Demon Barber of Fleet Street