what are the other areas of work explored by the actor who was replaced?
He is a filmmaker, musician and author.
Crispin Glover
Crispin Hellion Glover (born April 20, 1964) is an American actor, filmmaker, musician and author.

who played marty in back to the future Michael J. Fox what was the premise of the film? Marty McFly, a teenager accidentally sent back in time to 1955 in a time-traveling DeLorean automobile built by his eccentric scientist friend Doctor Emmett "Doc" Brown. what kind of cultural impact did the film have? "Back to the Future" has influenced or been referenced in a variety of media, including: "American Dad". does it have any sequels? Yes, "Back to the Future Part II". does it have same character mentioned above? Yes. was it played by same actor? Yes. were any actors from the first film replaced while making the sequel? Yes, Crispin Glover. who replaced him? Jeffrey Weissman.
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Crispin Glover [SEP] Introduction
Crispin Hellion Glover (born April 20, 1964) is an American actor, filmmaker, musician and author. Glover is known for portraying eccentric characters on screen, such as George McFly in "Back to the Future" (1985), Layne in "River's Edge" (1986), Bobby McBurney in "What's Eating Gilbert Grape" (1993), the Thin Man in "Charlie's Angels" (2000) and (2003), Willard Stiles in "Willard" (2003), Grendel in "Beowulf" (2007), Phil Wedmaier in "Hot Tub Time Machine" (2010), The Knave of Hearts in "Alice in Wonderland" (2010) and Mr. World in the Starz television series "American Gods" (2017–2021). In the late 1980s, Glover started his company, Volcanic Eruptions, which publishes his books and also serves as the production company for Glover's films, such as "What Is It?" (2005) and "It Is Fine! Everything Is Fine." (2007).