The first episode of the four part “The Case Against Adnan Syed’ on HBO was a gang busting hour setting up the mystery of whether Adnan Syed did or didn’t murder his ex-girlfriend. The documentary miniseries is based on the “Serial” podcast. The mixture of live interviews, reenactments, and audio narration makes for mostly compelling viewing. The second episodes tended toward the repetitive even with additional suspects popping up. With two remaining parts, it will be challenging to keep the viewer interested without intriguing red herrings.