A Guy Thing is a 2003 American comedy film directed by Chris Koch and starring Jason Lee, Julia Stiles and Selma Blair. It was a box office and critical failure.

Jason Michael Lee is an American actor, filmmaker, photographer, and former professional skateboarder. He is known for playing Earl Hickey in the television comedy series My Name Is Earl, for which he was nominated for Best Actor in a Musical or Comedy TV series in 2005 and 2006 by The Golden Globes, and Dave in the live-action films, Alvin and the Chipmunks (2007), Alvin and the Chipmunks: The Squeakquel (2009), Alvin and the Chipmunks: Chipwrecked (2011) and Alvin and the Chipmunks: The Road Chip (2015).