This is their first recording together, a gathering of duet performances from 2017 and 2018, chronicling a relationship that can sound like the intimate huddling of two old friends: whispered asides, excited exclamations, utterances coinciding with practiced harmony, followed by bursts of laughter. “Ain’t misbehavin’!” cries out one. “Waahhhh!!”, says the other. (That’s really Shepp speaking both parts—but you get the idea.)