Polenin

After the incident, Captain Vostrikov is tried for endangering the mission and disobeying a direct order, but Polenin comes to his defense, resulting in charges being dropped.

An engineering team produces a makeshift coolant system but Polenin discovers the submarine has been provided with chemical suits rather than radiation suits.

Captain Alexei Vostrikov ( Harrison Ford ), aided by executive officer Mikhail Polenin ( Liam Neeson ).

During his first inspection, Vostrikov discovers the reactor officer to be drunk and asleep on duty and sacks him, ordering Polenin to request a replacement.

Later in 1989, an aged Captain Vostrikov meets Polenin on the anniversary of the day they were rescued.

Polenin and Radtchenko learn back-up coolant systems are not installed.

Polenin regards this maneuver as dangerous and storms off the bridge.

Polenin, the original captain, and the crew have served together for some time but Vostrikov's appointment is alleged to have been aided by his wife's political connections.