Alanis Morissette is staying 'Up All Night.'

According to TVLine, Morissette will play a former member of Ava's (Maya Rudolph) music group, Sound LLC. Talk show host Ava's musical past was previously touched upon when Lonely Island's Jorma Taccone guest starred as her ex-boyfriend.

Morissette has previously done guest spots on 'Sex and the City,' 'Weeds,' 'Curb Your Enthusiasm' and 'American Dreams.' Her episode is set to air in early 2012.

In other casting news ...

'Law & Order: SVU' actress Diane Neal will practice law on 'A Gifted Man.' Neal will guest star as a defense attorney who takes Patrick Wilson's character to task on the stand. [TV Guide]

Jim Beaver is returning to 'Justified.' So far Beaver will return as Shelby for one episode as of now, but the episode count could increase to as many as 7. [TVLine]

'The Vampire Diaries' has found Klaus' brothers. Caspar Zafer and Australian actor Nathaniel Buzolic will play Finn and Kol, making their first appearance in Episode 13. [TV Guide]