Shamrocks electrical fire forces a diver's emergency ascent. The Clark's rookie ice divers gasp for air. The Lazy Gators Joe finds a huge picker, but their operation grinds to a halt when an accidentally sucked up boulder clogs the hose.

Halfway through the winter dredging season, tempers flare on The Clark. The Lazy Gators do a perilous freedive to try and recapture their only breathing apparatus, tangled underwater in a buoy. A new Shamrock diver tests his own nerve and Shawn's patience.

Winter is on its way out. Shamrock Phil gets one last chance. Clark's Zeke gets pinned up under the ice when he loses his weight belt. A Lazy Gator tender nods off, unaware of diver Jesse's distress call when his hose gets caught on an ice chandelier.

With the winter dredging season coming to a close, the crews scramble for one more dive before the cracking shifting ice sinks their operation or worse, traps a miner down below. The Clark's Zeke loses his weight belt and is pinned up underneath the ice.