Ben and Kate: 21st Birthday

When Ben decides to throw a birthday party for Kate against her wishes, her frustration soon turns into excitement when she realizes that Ben invited Molly, Kate's wild friend from high school, to her party. Meanwhile, Ben finds out that Darcy, the only woman he truly cared for, is moving into what used to be his and Darcy's dream home with her new husband, and Tommy comes clean to Kate about why he hates Molly.

Source: FOX