It was Junior Wells’ return to the Delmark fold; it was the titan Otis Spann’s last recording session. Junior’s regular band—Buddy Guy, guitarist Louis Myers, drummer Fred Below, bassist Earnest Johnson—filled the studio with blues legends, all at the top of their games. Finally on CD, this reissue of a free-flowing 1970 session adds seven bonus tracks to the original vinyl’s eight and is remastered with bright, warm studio sonics. Honoring the Monday night goings-on at Theresa’s Blues Bar on Chi-town’s south side, Southside Blues Jam features the deepest blue of blues, “I Could Have Had Religion” (wherein Junior blames a feckless lass for causing him to forsake the pulpit); blends autobiography with social commentary in the swaggering “Blues for Mayor Daley”; and soars with the warm, ad-libbed verbal jousting on “Trouble Don’t Last,” 7:54 of volcanic simmering featuring sly references to Skip James and Sonny Boy Williamson amidst Buddy Guy’s stinging guitar and earthy vocal, Junior’s tremulous harp and dark voice, and Otis Spann’s spot-on responsive fills on the 88s. That Theresa’s was a one-of-a-kind night spot is a point Junior and his buddies make with a vengeance. You’ll wish you had been there.