Philadelphia-based pianist Matt Mitchell makes his debut as a leader with Fiction, but the rising star already can be heard in the bands of Dave Douglas, Tim Berne, and John Hollenbeck. Here he's joined by Ches Smith on drums and vibes, and the two create a challenging 15-piece program that covers a broad swath of melodies, tempos, textures, and ideas. There’s nothing here that immediately jumps out as swing-based, and sometimes on first listen the two players sound like they're playing against each other (“Brain Color” and “Wanton Eon”). Yet that's due more to Mitchell’s willingness as a composer to push at boundaries and the density of ideas he uses to do it. It’s an often-challenging listen that starts with the driving “Veins” and ends with the dreamy “Narcotic Bases.” Sometimes the conversation is crystal clear, as it is on “Dadist Flu,” and listeners can follow along with ease as the players volley ideas back and forth. Yet easy isn’t always best, and this is certainly the case with Fiction.