When a commuter ship capsizes, the ED finds itself under water as the staff struggles to treat the influx of new patients and deal with bold new employees taking charge.

Lenox continues to rankle Archer as the two tackle their new roles; Ripley faces possible suspension over what really happened to Pawel; Goodwin is forced to make layoffs.

Hannah treats a woman whose undiagnosed condition threatens the lives of both her and her unborn child. Goodwin receives a chilling message while battling the hospital higher-ups.

A familiar face returns to the ED. Ripley and Charles treat a woman with a rare disorder. Frost suspects that his patient's father is lying about his daughter's condition.