SEASON 4, EPISODE 415 - When evidence of a pipe bomb is found in a suburban home during renovations, Rush reopens the case of a married couple killed in 1981 in what was termed an accidental gas leak explosion at the time. As she digs into the history of the couple and their friends, Rush learns that, ten years earlier, they had all been linked by their opposition to the Vietnam War. But secret feelings and illegal activities led to a rift between the friends, and Rush must sort out who may have placed the bomb in the couple's kitchen after a tumultuous ten-year reunion. Meanwhile, Stillman tries to remember his parenting skills while caring for his visiting grandson. Songs by legendary musician Bob Dylan are featured throughout the episode.