Filming had to be suspended on a film starring Kate Hudson when a deadly Irukandji jellyfish appeared on set.
Hudson, 27, was filming the movie's final scene
Hudson and co-star Matthew McConaughey were shooting Hollywood adventure Fool's Gold in Queensland, Australia when the venomous visitor was spotted.
"We have a marine expert to ensure everyone's safe and he found the jellyfish," said Hudson's publicist, Fiona Searson.
"It's an unusual problem to come across. Only in Australia, I suppose."
Despite being little bigger than the size of a peanut, the Irukandji jellyfish has been described by scientists as one of the most deadly creatures alive.
Little is known about it, except that its sting can cause severe pain, anxiety and a potentially fatal rise in blood pressure.
There is no antidote, but doctors in Queensland say magnesium infusion can fight the jellyfish's lethal venom.
The tiny, but deadly, Irukandji jellyfish
It became the subject of serious research when two tourists, an American and a Briton, died after coming into contact with the creature in 2002.
The marine biologist working with the film crew said swimmers needed to be warned and precautions may be needed on northern beaches, where swimmers wear lycra "stinger suits" in jellyfish-infested waters.
"You're going to at least have to inform tourism and tourists that there is the potential... I mean these animals have the potential to kill you," Jamie Seymour told ABC radio.
Ms Searson confirmed that most of the US cast and crew, including Hudson and McConaughey, have returned home until the final scenes can be scheduled.
The romantic adventure is due to be released early next year.