Eric Stoltz was actually hired to play Marty McFly in Back to the Future, and was replaced later with Michael J Fox.
Actor who got the part: Michael J. Fox
Eric Stoltz was in the lead for the roll of Jeff Spicolli. When Sean Penn showed interest, the role went to him instead.

Did you know that Eric Stoltz was not the only choice for this movie?
(click to learn more)