Limit Of Love: Umizaru 2006

Two years into his career as a Japan Coast Guard frogman, Daisuke Senzaki (Hideaki Ito) has matured into a seasoned diver destined to be among the corp's elite. But he is haunted by past failure and the emotional strain that accompanies a job of saving lives has cast doubts in Daisuke's mind that threaten to destroy his relationship with Kanna (Ai Kato).

The two lovers past on a sour note, right before a large ferry boat called The Clover, equal in size to a 9-story building, runs aground off the coast of Kagoshima. Daisuke and his diving buddy, Tetsuya Yoshioka (Ryuta Sato) has sent in to salvage what turns out to be an explosive situation.

A tear in the ferry's hull has caused the boat to flood quickly and heel to one side. Faced with 620 panicky passengers, 195 highly flammable vehicles and an inoperative onboard emergency system, the Coast Guard realizes that in about four hours, the ferry will sink. As Daisuke evacuates passengers, he catches sight of a familiar face among them - that of Kanna!