Kathy Griffin, Lance Bass

Kathy Griffin will guest-star on Drop Dead Diva, TVGuide.com has confirmed. 

 The comedienne — who will host TV Guide Network's royal wedding coverage — will play the sister of Kim (Kate Levering) and will clash with Jane's assistant, Teri (Margaret Cho).

ABC Family developing movie about lesbian teen who was banned from prom

Lance Bass, Clay Aiken and Amanda Bearse will also guest-star in Season 3. The trio will appear in the fifth episode, which primarily focuses on a gay prom. The ripped-from-the-headlines episode is based on Constance McMillen, the Mississippi teen who challenged her school board last year after it banned her from attending the prom with her girlfriend.

Bass will play a casting director who asks Fred (Ben Feldman) to appear in an energy drink commercial; Aiken will share the screen with Grayson (Jackson Hurst) when he takes the witness stand in a mail-order bride scam case; and Married... with Children alum Bearse will play a judge.

Exclusive: Drop Dead Diva lines up Season 3 guest stars

They join previously announced guest star Wanda Sykes, who will also play a judge, and McMillen, who will make a cameo as Sykes' bailiff.

TV Squad first reported the news.

Season 3 of Drop Dead Diva premieres in June.

Kathy Griffin's Insightful and Hilarious Take on the Royal Wedding will air Friday, April 29 — the day of the ceremony — at 8/7c on TV Guide Network.