The award-winning actor, who has starred in television, theater and film, celebrates his weight loss in a song-and-dance musical commercial for Jenny Craig during which he dons a tiny black spandex outfit.
"Throughout this campaign, Valerie (Bertinelli) has been taunting me to get into a bikini, or as she calls it, a 'mankini.' I thought, forget the mankini, if I lose the weight, let's take it all off!" Alexander joked in a statement. "With every diet I've ever tried, the first 10 pounds were always easy, and then they would come right back. Jenny Craig's program is the first one that helped me reach my goal. So, why not celebrate a little?"
In the spot, the 50-year-old former "Seinfeld" co-star shocks Jenny Craig spokeswoman Bertinelli with a revealing Broadway-style musical number featuring six professional dancers.
"I couldn't stop laughing in the rehearsals! I was losing my voice because I was having so much fun," Bertinelli said. "He looks amazing, and he definitely got one over me. He came up with this spot, and it's brilliant! A lot of people forget he's a Tony Award winner. It's really fun."
Celebrity Families of 2014 [PHOTOS]