Ben was spotted Tuesday with a script in hand in New Orleans as he prepared to begin shooting his new film, "Deep Water." Unclear if Ben's disheveled look -- messy hair, scraggly beard, wearing sweats and a stained t-shirt -- was part of his role. It's worth noting ... he's supposed to play Vic Van Allen, an attractive husband.

Anyway ... it's the first time we've seen Ben on the set since he relapsed nearly 2 weeks ago. As we've reported ... Ben was spotted leaving a Halloween party and clearly had trouble walking. He damn near fell before catching himself on an SUV.

Ben later acknowledged he stumbled in his effort to maintain sobriety. After leaving that party ... Ben hit up a casino. And, while he pocketed $1,500 in winnings in just 12 minutes of gambling, Ben could barely stand and nearly fell out of his chair. The next day, he said he vowed to get back on the straight and narrow.