Jon Hamm -- Completes Rehab Stint for Alcohol

Jon Hamm completed a 30-day rehab program for alcohol abuse, just days before the premiere of the last season of "Mad Men."

We're told Hamm checked himself into Silver Hill Hospital in New Canaan, Connecticut at the end of February. It's a high-end facility.

The final season is already in the can.

Hamm's people tell TMZ, "With the support of his longtime partner Jennifer Westfeldt, Jon Hamm recently completed treatment for his struggle with alcohol addiction. They have asked for privacy and sensitivity going forward."