'Freaks and Geeks' Star Linda Cardellini Joins 'New Girl' as Jess' Sister ... Will She Break Up Jess and Nick?

Linda Cardellini will join New Girl in the role of Abby, Jess' sister, TVLine reported on Monday. Cardellini's character will appear in Season 3, but there was no word when Abby would first show up.

Uh oh, fans of Nick and Jess, you know what Cardellini's casting means, don't you? She's going to break the couple up. Besides her Freaks and Geeks role, Cardellini was probably best known for playing the girl who broke up Cory and Topanga on Boy Meets World. When the actress first appeared on Mad Men last season, I made a joke about how she would break up Don and Megan, and — SPOILER ALERT — look who went and had an affair with Don.

Beware, Jess. Beware.