Visitors to a boating lake in Finsbury Park, north London were treated to a "Jaws-dropping" scene this weekend - as a 'great white shark' fin sliced through the water.
But, don't worry, it was just a stunt launched to coincide with Shark Week on the Discovery Channel.
With the lake opened for a private event, guests who had been invited to take part in filming at the park were treated to the unexpected sight of what appeared to be a great white shark fin slicing through the water as they rowed on the lake.
And some poor people looked horrified.
Joggers, dog-walkers and early morning commuters observed the watery encounters from the safety of the shoreline, before realising something fishy was afoot.
Luckily for the boaters, the stunt was a set up using a hand-carved polystyrene fin mounted onto a 3m tubular frame, with internal ballast and flotation devices to guide the shark. The prop was created by BAFTA award-winning art director and special effects designer Jamie Campbell, renowned for his work on Sea Monsters and the original Walking with Dinosaurs.
A macabre installation of a rowing boat - with a huge bite taken out of it - was placed on the boating lake island, to add to the scene.
A diver and medic were on standby near the shallow waters and one person in every boat was aware of the prank.
A spokesman for Discovery Channel told Aol Travel: "When you go for a gentile early morning ride around the shallow Finsbury Park Boating Lake, the last thing you would expect to encounter is one of nature's most renowned predators. All of the boaters saw the funny side and we can assure everyone that it is perfectly safe to go back in the water!"
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