Tony winner Kristin Chenoweth, Angelica Vale and Gina Gershon will all guest star on the season finale of ABC' s award-winning comedy, Ugly Betty, Thursday, May 17, (8:00-9:00 p.m., ET) on ABC.

In the episode, "East Side Story," Chenoweth will play Diane, an orthodontic technician who loves romantic comedies and becomes overly involved in her patients' lives include Betty's.

Vale, who stars as Lety in the hit Mexican telenovela "La Fea Ms Bella," will guest star as her assistant, Anglica.

Gershon will reprise her role as cosmetics mogul Fabia, who turns up at Mode to once again torment her nemesis, Wilhelmina Slater.