The opening scene of Lazarus's first episode transports us back to 1998, a year marked by unfathomable tragedy for Joel Lazarus. As a masked figure sprints from the bedroom, leaving behind the lifeless form of his sister, Sutton, Joel cradles her lifeless body, horror etched on his face. He rushes to his father, Dr. Jonathan Lazarus, to deliver the devastating news, his voice shaky with shock and grief.
Flash forward to the present, where the serial killer responsible for Sutton's demise has finally been apprehended. However, this news brings little solace to Joel, who finds himself in the secure psychiatric ward interviewing a murderer named Arlo. Arlo's delusions of speaking with God and his conviction that Joel is a fake believer in the almighty, are met with a further shock: the suicide of Dr. Jonathan Lazarus. But was it truly a suicide? The doctor was known to not own a gun, leaving behind only a cryptic clue: a stool and the words "it's not over." A newspaper clipping of Sutton's murder is also found, its headline announcing the suspect's release from custody.
Determined to uncover the truth, Joel delves into Sutton's room, searching for answers that seem elusive. Along the way, he reunites with Seth McGovern, his steadfast friend and an on-again, off-again fling for his sister, Jenna. They take refuge in a seedy dive bar, where they meet Bella for the first time. Bella is Joel's ex-wife, and the air is thick with unspoken resentments and unfinished business. The tension between them is palpable, as if every moment of their past is weighing on them.Joel's disdain for Bella's new husband, Paul, is palpable. He views Paul as a golf-obsessed individual with whom he has little in common. The two share a child, Aidan, now a 15-year-old teenager.
At Dr. Lazarus's office, Joel encounters an unsettling visit from Cassandra, a disheveled sociopath who invades his space uninvited. She divulges her dark thoughts and feelings as if she's in a regular therapy session, mentioning her contemplation of murdering her boyfriend, Neil. There's also a man stalking her, and it's all very unsettling. However, before Joel can process this fully, Cassandra vanishes into thin air. Was it all a vision?
Joel delves into Cassandra's file, which dates back to 1999 and contains an address that piques his curiosity. He quickly learns that Cassandra has been murdered and passed away 20 years ago. Confirming this online, Joel discovers that her killer remains unidentified. Of course, he believes there's a connection between Cassandra's and Jonathan's deaths.
Joel shares his thoughts with Seth, a police officer who has access to archived files. He asks Seth to sift through the files from 1999 to see if there's any connection to follow. Initially hesitant, Seth is persuaded by the promise of a pint at the pub.
As Jonathan's body is released and his funeral attendees gather, a shaggy-haired individual named Sam Olsen watches from afar. Sam was initially accused of killing Sutton but was later cleared of all charges.
However, for the moment, Seth returns with some diggings into Cassandra's past. As far as he can ascertain, there appears to be no connection between Cassandra and Jonathan outside of their sessions. The case, at first glance, seems straightforward—trouble found her, trouble killed her, case closed. He says, with a defiant air.
That night, Joel suspects a hooded figure lurking in the streets behind him, so he gives chase in an attempt to track the mysterious figure down. The hooded man, wearing a mask, piques Joel's curiosity as he believes this individual might hold a crucial clue. Unfortunately, he loses sight of him at the graveyard—of all places.
Naturally, Joel finds himself at Sutton's grave where the masked man unveils himself to be... Joel himself? This triggers a trippy dream sequence as Joel finds himself back in Jonathan's office. This time, Jonathan approaches and points out that there are others who were murdered like Cassandra who will come to him.
