The movie A Guy Thing is a romantic comedy released in 2003. It is directed by Chris Koch and stars Jason Lee, Julia Stiles, and Selma Blair. The story revolves around Paul Morse, a man who wakes up the morning after his bachelor party to find himself in bed with Becky, a beautiful girl he meets at the party. Paul cannot remember anything that happened the night before, but he soon realizes that he is not alone in his hotel room, and he quickly tries to escape before Karen, his fiancée, finds out.
As Paul tries to untangle the web of lies he has created, he becomes increasingly anxious and confused. He tells Karen that he spent the night at a friend's house, but things get complicated when Becky turns out to be Karen's cousin. To make matters worse, Paul's parents are in town, and they are pressuring him to get married as soon as possible.
As the truth starts to come out, Paul must come to terms with his feelings for Becky and Karen, and figure out how to make things right with both of them. The movie is filled with humorous situations and mistaken identities, as Paul tries to keep his secrets hidden. It is a light-hearted comedy that explores the complexities of relationships and the lengths people will go to keep their loved ones happy.