Dimension Films has signed Anna Paquin and Kristen Bell to join Wes Craven's "Scream 4," which recently added more than two weeks to its shooting schedule.

Set to launch a new trilogy in the studio's popular slasher franchise, "Scream 4" is now filming in Michigan with Craven ("A Nightmare on Elm Street," "Scream 1-3") at the helm.

The sequel was expected to wrap shooting Labor Day weekend; however, its sizable 140 page script may explain why the studio extended filming to Sept. 24, according to The Hollywood Reporter.

Paquin ("True Blood") and Bell ("Veronica Mars"), whose roles remain unclear, join recent cast additions of Hayden Panettiere, Emma Roberts ("Aquamarine"), Adam Brody ("The O.C.") and Alison Brie ("Community").

Roberts will play Jill, a cousin of Neve Campbell's character Sidney. Panettiere ("Heroes") will play Kirby, a film geek and Jill's best friend.

Brody will play Hoss, a green detective, and Brie will play Sidneys personal assistant whos jealous of Sidneys fame.

In addition to Campbell, David Arquette and Courteney Cox-Arquette are also reprising their roles from the first trilogy, with Kevin Williamson ("The Vampire Diaries," "The Faculty") returning to script.

The original "Scream" trilogy rocketed into pop culture, earning close to $300 million domestically.

"Scream 4" hits theaters April 15, 2011.