Venturing 600 miles north, the fleet encounters subzero temperatures and freezing spray. Sig sets into a tidal surge, but the extreme forces leave Clark injured. While Keith fishes through pain, Jake's risky pact unravels when a key man goes down.

After six relentless weeks at sea, man and machine push past the breaking point. While Keith seeks medical care in Anchorage, the Wizard loses steering in 20-foot seas. Rick fears the worst as he takes on water, and Clark finds Sig unconscious below deck.