Jessica Biel Jessica Biel

When New Girl returns for its fourth season this fall, Jess (Zooey Deschanel) will be facing some competition from... Jess?

Actress Jessica Biel will guest-star in the Season 4 premiere, and her character won't find a friend in Jessica Day, has confirmed. Biel will play a sexy scientist named Kat who fights with Jess over the same guy.

Secret celebrity weddings

In the episode, the roommates will have a competition to see who can score at the last marital bash of the wedding season. Naturally, adorkable Jess wants to hook up with the man who is also being pursued by the "hottest scientist in the world."

It will be a long overdue return to television for Biel, who starred in 7th Heaven in the late 1990s and early 2000s. Biel made a cameo on Saturday Night Live in 2009, but has mostly focused on film, with roles in Total RecallNew Year's EveThe Illusionist, and Playing for Keeps.

If you were the lucky man, who would you choose: Jessica Biel or Zooey Deschanel?

Watch This Tonight — See why Who Do You Think You Are? is today's editors' pick: