Mass Destruction.

the episode starts off with a flashback of "jcjenson" scientists at the "cabin fever cathedral" trying to keep the "absolutesolver" (who has possessed "nori") under control. an intern names "mitchell" accidentally wears the uniform of a scientist called dr. chambers, causing the team to call upon him. the solver takes the distraction and tries to attack the scientists before it's put at bay for a short time. "dr. ridley," who resembles a priest, holds a "usb in the form of a crucifix" whilst mitchell is handed yeva's id and goes to get her. after retrieving "yeva," he locks her out and discovers that the other scientists were killed by the solver who dragged them into a hole. the flashback (which was actually a video) ends as a drone (in the form of a heart) crosses off an area on a map as they go to the hole with a pickaxe.