Buck jumps back into the dating scene but fears he will return to his old ways; a woman goes to great extremes on a freeway overpass to get the attention of her husband; a couple have a car accident on their wedding day.

The first responders deal with a calamity at a chocolate factory; a mail bomb explosion; Eddie receives some surprising news from Shannon; Maddie contemplates her future in the call center.

Athena and Bobby set off on their honeymoon cruise, but when duty calls, their vacation is put on hold. Meanwhile, a fighter jet traps a civilian, and an unusual incident leaves a couple stuck together.

The disastrous cruise continues when Bobby and Athena respond to the ship's explosion, racing to aid injured passengers. Meanwhile, Hen questions her instincts in a life-taking call and grows concerned about Athena and Bobby's whereabouts.

With each moment becoming critical as the ship is flipped upside down, Athena and Bobby take charge, seeking methods for rescue while navigating efforts to guide survivors to safety. Meanwhile, Hen defies protocols in her search for Bobby and Athena.