Ben gets told that he is going on a cruse ship because Murray (enemy) was planning something but they didn't know what it was they just knew he would be on the Emperor of the Sea cruise ship. Mike, Erica, Catherine and Alexander would all be pretending to be his family which would be less suspicious.
Murray is using the nuclear engine as a giant bomb and is going to blow it up
they get on the cruise and Alexander feels sea sick
stop!!!!
Ben gets thrown overboard by Dane which is helping Murray with his evil plan and Mike sees him get thrown overboard and comes to rescue him but the ship leaves and they are left on the island wear a very nice drug dealer helps them get back to the cruise.
Ben figured out that Murray's evil plan was to use the nuclear engine of the cruise ship and blow it up with a bomb so he tells Erica, Catherine, Mike and Alexander in their small dorm on the ship.
they catch Murray when he is trying to escape in a plane
with a few minus to spare they stop the timer for the bomb( spoiler but i will not put this in the trailer)