My top five cruise movies

I was chatting with some friends last night about the amount of times a cruise ship gets used in a movie either as a setting or as a plot device and someone made a comment that there always seemed to be hundreds of movies featuring cruise ships about.
As one, everyone turned to me as though I'd be able to list every movie ever made to feature a cruise ship. With a bit of thought though I was hard pressed to come up with even ten, let alone ten good ones.
It's with that in mind that for todays post I've listed my top five favourite movies featuring cruise ships. Bear in mind it was a slim list I was picking from so if you can come up with a better top five, or you can even think of some cruise movies I've missed, feel free to add them below.