Scuba diving, swimming, snorkeling and even cliff-diving are all popular holiday activities you can enjoy in the water - and now underwater cave diving has become a thing too.
Brett Roth did exactly that when he decided to explore the underwater caves near Laguna Beach in California, and he documented his experience in this film.
See also: Photographer captures incredible cave light pictures
Before heading into the deep we see Roth looking over his shoulder in both directions as he appears to check out the swell of water approaching him.
Then, taking one deep breath Roth, who appears to be holding a selfie stick, plunges into the depths of the watery cave only resurfacing when an underground air pocket appears.
See also: Sea turtle hugs diver after being cut free from fishing net
His feat is especially impressive given that he was only armed with a pair of diving goggles and some flippers to help ropel him into the deep.
As Roth glides through the water he seems to encounter a narrow opening before entering another shadowy area with rock outcrops bordering the camera's view...