Back To Booze? Jon Hamm Caught Having 'Multiple Drinks' After Rehab Stint — Bar Patron Tells All

Jon Hamm appears to have lost his struggle to stay sober since his rehab stint at a Connecticut facility one year ago. The Mad Men actor — who is in town shooting the crime thriller Baby Driver — was caught at an Atlanta lounge Sister Louisa's Church of the Living Room & Pink Pong Emporium, tossing back one drink after another while on a date with a young mystery blonde.

"An alarm went off in my head because I knew he'd been to rehab last year," the eyewitness told Star. "They moved from the bar to a couch and sat there drinking multiple gin and tonics. Jon didn't seem to care who saw. He wasn't trying to hide whatsoever."

"She hung onto him the entire night and occupied all his attention," the eyewitness told Star, adding the pair finally left the bar at closing time.

As Star previously reported, Jon ended his 18-year relationship with girlfriend Jennifer Westfeldt last July, but friends speculate this isn't the only reason for the star's relapse. Instead, what could have triggered the slip was his career stress: he just finished four films back-to-back and already has another in motion, a political thriller High Wire Act.

"His appearance was alarming," the Louisa's patron said. "He looked like a completely different person. He'd lost a lot of weight and his skin was so pale. He'd really let himself go."

"He had a huge presence on the small screen with Mad Men, but now he's branching out into movies, and he's really thrown himself into his work since rehab," a pal told Star. "He may feel like it's all work and no play. In fact, he recently admitted it was getting harder to ignore that little voice in his head that says, 'One drink won't hurt.'"

Star readers know that Jon has admitted that his childhood was not an easy battle itself: his 35-year-old mother lost her fight with cancer and his father frequently skipped town. "Life throws a lot at you sometimes,” Jon has said. "That's why you have family and friends and co-workers to help."

But now, those friends and family fear the A-lister is putting his career in jeopardy by hitting the bottle again. "We're all incredibly concerned," his pal said.