WARNING: If you don't want to know what happened in this episode, don't read this photo recap!
We’ve gone back in time, six days before the earthquake that upended the physical realm and enabled the dead to return to their living counterparts, to be exact. Dr. Barker is at the Lambda research facility and has just been given orders to execute an experimental research machine dubbed Collider (a particle accelerator) ahead of schedule. She does, but it's bad timing, and it sets off the earthquake that shudders through Port Moore.
Meanwhile, as the scientists have little to do during the quarantine, Dr. Barker returns to the accelerator room. There she's haunted by the ghosts of some of the deceased who, in the afterlife, have tried and failed at second careers as Emergency Medical Technicians.
Dr. Barker thinks that the particle accelerator, combined with the earthquake, may have unleashed anti-matter everywhere — in the form of the apparitions haunting people. So she and her theoretical physicist Paolo break orders to go investigate the quarantined Collider room.
One of the ghosts, Chloe, heckles Dr. Barker, revenge for not saving her from the explosion. The spectre then sends a standing light crashing her way. Dr. Barker suffers from a panic attack, and passes out.