HerbertMMarx · CC BY-SA 3.0

Eddie Deezen made a career out of playing the nerd, a stock type he turned distinctive across films including Grease, 1941, WarGames and Grease 2 in the late 1970s and early 1980s. He later became a fixture of Saturday morning television as the voice of Mandark on Cartoon Network's Dexter's Laboratory, and reunited with director Robert Zemeckis in 2004 to play the Know-It-All Kid in The Polar Express.