Don't worry – that's just an awesome optical illusion.

Australian photographer Gary Brennand starting blowing minds when he posted this photo to Instagram after a Great Barrier Reef dive off Cairns, Australia. Brennand – a PADI course director according to his Facebook page – writes that he was thrilled to see the famous humphead wrasse Wally open his mouth and did not realize the diver in the back until later.

• Related: The eight iconic species of the Great Barrier Reef

Humphead, or Napoleon, wrasse are known for their size – some grow as long as seven feet – and propensity to swim right up to divers. Wally, commonly seen by divers on the Great Barrier Reef, is one of the most famous wrasse in the world.

To see more of Brennand's stellar photography, check out his Instagram and website.

Want to see more? Check out this awesome video of sailfish hunting off the coast of Mexico.