A semi plows off a bridge, leaving a trailer and three RVs dangling over a raging river; John must get holiday traffic moving and prove himself on a multi-part recovery unlike anything they've faced.

A downpour of freezing rain covers Hope and the Coq in a thick layer of ice, cutting off communication and crippling Jamie's operations; Ken Monkhouse heads to a job up a remote, ice-covered hill and re-lives the worst day of his life.