ACK....there so many different plot lines that connect in this series. The victims are connected to the killer(s) who are connected to the detectives in the police department where Dexter works as a forensics specialist. Every episode connects to the next. I can't give you any specifics without giving things away. The first season has a DEFINITE story arc and the second season has a DEFINITE story arc. The third season has just started, but I'm guessing the pattern will continue.