Walter has acted in six Jonathan Demme films: Something Wild (1986), Married to the Mob (1988), The Silence of the Lambs (1991), Philadelphia (1993), Beloved (1998), and The Manchurian Candidate (2004). He has been directed by Danny DeVito in three films: Matilda (1996), Death to Smoochy (2002), and Duplex (2003). He acted with and was directed by Jack Nicholson in The Two Jakes (1990). He and Nicholson have appeared in nine films together, beginning with Goin’ South in 1978.

He appeared in a small role with Clint Eastwood in the 1982 film Honkytonk Man and has coined the phrase “Right Cheer” (as in right here) while playing a service station attendant, also attributed to Andy Griffith on his first comedy album “What it Was, Was Football” (1953). As well as “Make ‘Em Bounce” (as in happy) from the movie Raggedy Man. His portrayal of Miller, the philosopher mechanic of Alex Cox’s Repo Man, earned Walter a Saturn Award in 1985 for Best Supporting Actor. In the 2000 film Erin Brockovich, Walter played Charles Embry, the PG&E employee who supplied the memo that tied an executive at the PG&E corporate headquarters to knowledge of the Hinkley station water contamination.