A man wakes up in a hospital and realizes that everybody on earth is dead. Though he thinks. He then starts doing weird stuff like having sex with dead bodies and smashing stuff.
San Francisco, USA, 15 seconds after it happens: Julie and Lee stand shocked at the fallen people surrounding them in a parking garage before Lee risks a similar fate.
San Francisco, USA, one minute after it happens: With a small group from Level 6 of the parking structure, Kenneth takes Lee away from the sprinklers to a van, hoping to save him.
Oria, Italy, two years after it happens: In a desolate village, Matteo tries to help a man injured in an accident, but he realizes that getting the medicine he needs will not be easy.
Mumbai, India, five months before it happens: Dr. Gurveer prepares to implant H+ in Leena so the biological parents can track her pregnancy from abroad.
San Francisco, USA, 45 minutes after it happens: Kenneth races to save Lee's life with spare wiring and circuit boards over the objections of Francesca, a soon-to-be board-certified neurologist who can't believe what she's seeing.
Helsinki, Finland, seven years before it happens: Now in a physical relationship with Manta, Topi goes to a crime scene that is technically out of his office's jurisdiction. A look at the victim offers a tantalizing clue.
Helsinki, Finland, seven years before it happens: Sharing a growing intimacy, Topi and Manta go on a hike, but Manta refuses to share all that's on her mind.
Portland, Oregon, USA, five years before it happens: After pitching her new software venture to a corporate board, Breanna privately meets with a younger Kenneth to offer an opportunity.
San Vito, Italy, two years after it happens: Someone with an interface observes Matteo outside the gates of a base. Later, Matteo returns home and has a flash of insight.
Mumbai, India, three months before it happens: In a conference with Dr. Gurveer, Leena is asked to adjust her sleep schedule to match Breanna's work demands.
San Francisco, USA, two days after it happens: Brian, a young boy, finds his mother in the parking structure and describes the chaotic world above. Kenneth gives him a special assignment.
Helsinki, Finland, seven years before it happens: Drunken Topi stumbles onto a fragment of conversation online and is suddenly messaged by Manta, whom he meets at their bar.
Oria, Italy, two years after it happens: After experiencing a vision, Matteo is awoken from his trance by someone he has been close to but never met, standing in the rain.
Dublin, Ireland, four years before it happens: Just before Kenneth leaves to observe the human trials of H+ in South America, Breanna feels there is something he needs to hear.
Southern Italy, two years after it happens: Matteo and his female passenger come to a roadblock manned with armed thugs. The passenger suddenly has an eerie insight and knows just how to save their lives.
Dublin, Ireland, three weeks before it happens: As we see what Connal sees through his connection, Breanna grows suspicious of all the time he spends on his H+.
San Francisco, USA, one week after it happens: Finally out of the parking structure, Kenneth needs to lead his people out of the H+ reception area, but Jason holds him at gunpoint.
Tierra del Fuego, Chile, four years before it happens: Kenneth visits the lab where the H+ technology is being synthesized onto the map of the human mind.
Oria, Italy, three months before it happens: In priestly robes, Matteo faints as he meets Simona in his church. When he wakes, he blames the incident on his body adapting to his new H+.
Northern California, USA, two weeks after it happens: As Francesca and Simona reconnect in a cabin, Kenneth preps Anthony on what to do while he's gone.
Dublin, Ireland, three years before it happens: After Kenneth skips his own party, Breanna seeks him out at his apartment. Kenneth reveals why he's been on edge.
London, UK, nine years before it happens: During an underground medical experiment, a figure presses Dr. Gurveer to bring his new implanted chip to full power on an unlikely test subject.
Dunbara, Republic of Congo, one year after it happens: Topi and the young soldier search for Dunbara, a village that was burned to the ground long ago.
Northern California, USA, three years before it happens: Having raised the stakes and kidnapped an enemy of their cause, Jason and his clan of neo-Luddites tell the hostage what they want.
Mumbai, India, eight months after it happens: In post-disaster India, Dr. Gurveer visits Leena's small village with one goal in mind, and he encounters a reaction he doesn't expect.
Northern California, USA, three years before it happens: After having a dream, Kenneth wakes with an insight that drives him to alert someone immediately.
New York, USA, eight years before it happens: Jason wants a fair settlement for the harm caused to him by LPW, a biotech firm. But the LPW lawyer interprets things differently.
Yozgat, Turkey, one year after it happens: Riding with Dr. Gurveer and baby Vadish in the backseat, Leena connects with Connal for the first time in a year... and makes an unsettling discovery.
Northern California, USA, two weeks before it happens: While Jason is rallying his troops, his mechanical body brace gives out, and he is unable to move his arms and legs.
Southern Alaska, USA, one year after it happens: Kenneth, Simona and Francesca reach the Alaska Data Center, where there is a surprise waiting for them.
The Vatican, Italy, two years after it happens: Carrying a desperately sick Manta, Topi bursts into where Dr. Gurveer is testing and training baby Vadish.
In the season finale, Kenneth has something else up his sleeve for Jason. In a flashback to the moment of the massive virus attack, we find clues to the deeper cause.
