One of my favourite Peter Sellers films is his penultimate movie, Being There.
It was what some would call the Forrest Gump of the late 1970s. Sellers plays a gardener called Chance, who is discovered on the streets of Washington DC and is thought to be an economic genius called Chauncey Gardener! Sellers was nominated for a Best Actor Oscar for this role but lost out to Dustin Hoffman for his role in Kramer Vs Kramer (although if the academy had any idea that Sellers had less than six months to live, one wonders whether they would have changed their minds).
Anyway, here is a trailer for the film, courtesy of YouTube (It's worth watching and Sellers gives a very restrained performance for once)