Dave's patience is tested when Gemma's freeloading sister, Brittany (Deborah Baker Jr.), suddenly shows up with plans for an extended stay. Also, Calvin grows frustrated that Malcolm is still living at home, even with a new job

Gemma's troublemaking sister, Brittany, returns, claiming she's turned over a new leaf, thanks to a surprising new business venture. Also, Dave finally convinces Calvin to accompany him to an escape room, where they both get more than they bargained for.