new york city Kirstie Alley dress weight gown david letterman talk show

Kirstie Alley is shrinking before our eyes!

The gorgeous Dancing With the Stars alum stepped out in a bright purple dress that perfectly accented her newly-svelte frame, as she made her way into the David Letterman Show on Monday.

Before heading out the door, Alley hurriedly Tweeted: "Madly scrambling to get ready to confront my estranged lover..David Letterman…I shoot it tonight. It airs Thursday. I gotta zip outta NYC."

Since finishing at an impressive second place in the DWTS competition this year, Alley has kept up her rigorous workout routine, and it's definitely paying off!

A far cry from the Fat Actress, circa 1998!

Find out what Alley Tweeted when she left the David Letterman Show last night, after the jump ...