Heights, crowds, small spaces... How does a psychologist handle three phobia sufferers on a cruise ship in the Gulf of Mexico?

Dr. Nicholas Brandon of Houston thought a four day cruise could be a graduation of sorts for patients in his therapy group, for those looking to take the final step out of their self-imposed prisons. But the wisdom of this comes into question when ruthless Lebanese terrorists seeking to make their mark on the world commandeer the ship. It's now in Nick's hands to ensure that he and his patients can survive and escape their new prison.