Fringe investigation is triggered when a patient at a mental institution undergoes an impromptu brain surgery that unexpectedly leaves his brain exposed. Despite the unthinkable circumstances, the patient's condition and sanity miraculously improves before the Fringe team arrives. While Agent Dunham and Peter scan surveillance tapes, Olivia recognizes a familiar face as Thomas Jerome Newton, the leader of the "shape-shifters." As similar cases stack up, the Fringe team heads back to the lab to determine exactly how patients are being cured. Walter's brains are put to the test and William Bell resurfaces.