A small-town English teacher is shown a portal through time to 1960... and asked to stop Lee Harvey Oswald from assassinating John F. Kennedy in 1963.
While Abraham and Vasiliy try to obtain the Lumen, Kelly disguises herself as a human and continues her search for Zach.
With the couple finally in a happy place, Vincent considers proposing to Catherine. But when she discovers a case involving someone turning innocent people into superhuman beings, the two have to find a way to stop them. Meanwhile, Tess is upset over J.T. stalling his recovery because of his bewilderment over how he was able to survive.moreless
Cat fears Vincent must die in order for Gabe to be stopped in the Season 2 finale.
Gabe tries to woo Cat by taking her on a romantic date.
Cameron continues to use dodgy tactics on Ava's case; Rachel visits law schools; Mike reflects on the past.
Dr. Leekie gives Sarah pause about seeking revenge after Kira's life is threatened. Cosima must choose sides when she realizes the truth about Delphine. The truth about where Sarah came from changes everything.moreless
Annie and Auggie head to Spain on a DPD mission to acquire a computer virus.
A break is finally achieved in Sarah Holy case when Mitch, Ray, Tammy and Abby put all their information together and discover that Noble Insurance, under the direction of Kevin Stack, is systematically killing terminally ill patients in order to save insurance money and that Sarah, using her medical training, is the one who commits the murders. Mitch asks for a meeting with Sarah to confront her with what he knows.
Meanwhile, Mitch's first paying client, Gerald Sykes, is in jail charged in an ABM robbery and shooting. Despite DNA evidence, Gerald protests his innocence claiming he was not there. When Mitch tells him that he needs a viable defense, Gerald changes his initial story to claiming he was there but was the victim, not the robber.
When attempts are made to save the man who collapses in front of Abby fail due to CPR and the 911 system not working causes both Abby and Lina to look into Y why 911 responses are being delayed. The Kowalski family gets a surprise win their son Donnie tells them he wants to try out for the swat team causing secrets to be revealed that may cause more tension within the family.moreless
Cameron and Nina fall under the influence of a cult leader who can make his followers see visions of Heaven... and feel the suffering of Hell.