Valerie Bertinelli has the law on her side! ET went on the set with Valerie as she guest starred as a look-a-like of herself on ABC's "Boston Legal!" And she opens up about her weight loss!

She plays a cattle rancher who is suing the FDA and catches the eye of none other than William Shatner's womanizing character, Denny Crane -- only Denny thinks the cattle rancher is actually Valerie Bertinelli!

Valerie reels with excitement about the new role because she calls herself a "big fan" of the show. The actress also tells ET what her amazing weight loss has done for her self-esteem.

"I didn't just lose weight," Valerie says. "I lost this albatross around my neck or this person that I thought I was that I really wasn't. I lost shame; I lost insecurities."

As for her other entertainment endeavors, Valerie is set to star in a TBS sitcom and release a new book! Valerie's first book was titled Losing It, and her next book will be called Finding It.

Watch the video for more on Valerie's happenings and see what takes place when she shares the spotlight with William Shatner!