Passengers aboard the German cruiser Mein Schiff 1 set off on a 12-metre catamaran on Sunday afternoon to watch the sun set over the Dominican Republic.
But a leak sprang on the watercraft, named Boca de Yuma 1, flooding it and causing it to sink just off the shores of Samaná Bay.
Footage shows holiday-makers – including elderly people and children – floundering in the sea as rescue crews arrived.
No one was injured.
The cruise had departed Jamaica the day before and was set to arrive in Mexico on Monday, according to monitoring website CruiseMapper.
TUI Cruises, which operated the cruise, told German tabloid Bild: ‘The excursion catamaran from an external provider sank during an excursion.’
