Shiver me timbers!

Tourists had the shock of a lifetime when the “family party” pirate boat they were sailing off the coast of Turkey tilted sideways, before rapidly sinking underwater — forcing all 148 people on board to jump for their lives.

The Big Boss Diamond boat, which promises “magical moments of a lifetime,” set sail from the Turkish resort city of Marmaris Friday for a five-hour trip to Paradise Island — but things quickly went awry after it weighed anchor.

“The engine blew,” said one of the passengers, The Sun reported.

Dramatic footage, captured by tourists on nearby boats, showed the vessel tipped over 45 degrees to one side, as a panicked bathing suit-wearing man jumped out, legs first.

Lifejacket-clad tourists surrounded the pirate ship in the Mediterranean turquoise waters, as rescue boats made their way towards it.

The boat, which boasts that “parents can have a party upstairs” while the kids play, had 20 children among its passengers.

It became almost completely submerged within an hour, only its pirate masts poking out of the deep blue sea, as debris from the ship floated all around it.

“Dear guests and friends, thank you very much for asking and worrying about us,” Big Boss Diamond wrote on Instagram after the traumatic experience.

“We are all safe and fine,” it said, adding a different ship serve operate its party tours while Big Boss Diamond is “fixed up,” without saying anything about what caused it to sink.

Social media posts from the tour operator from the days before the accident showed bikini-clad tourists dancing, drinking and spraying water on each other to the tune of “Pump it Up” as a man dressed in pirate attire worked up the crowd, who paid $60 for unlimited drinks.

No one was injured or died, according to the Muğla Governorship, who coordinated the rescue operation.