S4E22: The One with the Worst Best Man Ever

Joey convinces Ross to pick him as his best man instead of Chandler. He throws a great bachelor party, but the next morning he's shocked to find out that the wedding ring is missing and he suspects that the stripper stole it. Meanwhile, Phoebe is experiencing major mood swings due to her pregnancy and the girls decide to throw her a baby shower to cheer her up, but it only makes matters worse.