I love Sellers but the truth is he made a lot of crappy movies. His handful of great films have already been mentioned. Outside of that, there are a bunch of movies where he's the best or most interesting thing in them.
By most accounts, he was difficult to work with. His idiosyncrasies got more extreme as he aged which had an effect on his work. He also seemed to like getting paid as a leading man which influenced the roles he chose in the latter part of his career. I think his last decade as an actor would have been more memorable if he had transitioned into character parts. The 1970s were a great decade in film; there were lots of filmmakers who could have used Sellers effectively in supporting roles.
Roles turned down by Peter Sellers:
10
Turned down the leading role again and again, then filmed a cameo that was eventually cut.
Actor who got the part: Dudley Moore
Dr. Strangelove
Unable to play a fourth role in the film, Major T.J. Kong, due to a broken leg.
Actor who got the part: Slim Pickens
Kiss Me, Stupid
Director Billy Wilder was forced to replace the ill
Peter Sellers
as the show biz lowlife stranded in a small Nevada town.
Actor who got the part: Ray Walston
Oliver!
Considered a prime candidate to star as Fagin in the Sir Carol Reed-directed
movie version of the hit musical play.
Actor who got the part: Ron Moody
The Private Life of Sherlock Holmes
Sellers was originally director
Billy Wilder's top choice to play Dr, John Watson, but Wilder ultimately chose a lesser-known and less costly actor.
Actor who got the part: Colin Blakely
The Producers (1968)
Director
Mel Brooks says he first offered Sellers the role of scheming, down-on-his-luck
Broadway producer "Max Bialystock."
Actor who got the part: Zero Mostel
The Twelve Chairs
Mel Brooks wanted Peter Sellers for a role in The Twelve
Chairs.
