TV viewers know him as the rough-hewn guy in hat and glasses helping Dr. Drew on Celebrity Rehab, but decades before that, Bob Forrest won the love of music lovers (mid-’80s–early-’90s vintage) as leader of the literate and shambolic rock band Thelonious Monster. Then he fucked everything up. Forrest’s music, fuckups, and amazing, ongoing second life as a hugely influential addiction counselor are covered in Bob and the Monster, Keirda Bahruth’s documentary that screens tonight at the Uptown. The film will be followed by the first Seattle performance in 20 years by Thelonious Monster. (SIFF Cinema at the Uptown, 511 Queen Anne Ave N, www.siff.net, 8 pm, $15)