A shocked diver was photobombed by a sea beast "the size of a van".
Chris Bakon was diving for rock lobster when his friend spotted a menacing fin on the surface.
"We initially thought it may have been a great white shark so we went to check it out," he said.
But what the pair, who were fishing off Ship Stern Bluff in southeast Tasmania, Australia, encountered was a sunfish - the largest bony fish on Earth.
"The fish seemed huge underwater; the size of a van easily," he said.
"At first when I was swimming with it I was a bit intimidated due to the size, but after a few seconds I calmed down and was just in awe.
"It was such a magical thing to see underwater."
In Chris' footage, he turns the camera on himself and captures the mighty sunfish swimming behind him.
He also films the creature with one of its sides turned towards the surface, soaking up the sun's rays in a bid to regulate its body temperature.
The sunfish is known for its huge size and its freaky appearance, with some saying it looks like half a fish due its lack of a tail fin.
For Chris, a former soldier who served with the Australian army in the Middle East, encounters like these help heal the scars of a traumatic past.
He now documents his underwater experiences on Facebook and YouTube, where he is known as Tassie Adventure Man.
"I had no idea about these fish and definitely wasn't expecting to see one," he said.
"I feel pretty lucky to experience it.
"I started diving and opened the Tassie Adventure Man page to help manage my PTSD (post-traumatic stress disorder) and mental health.
"They keep me motivated, and keep the stress and triggers at a manageable level for me."
Mr Bakon, 39, hopes he can help others this way.
He said: "I found once I started diving, all my anxiety and PTSD would just disappear.
"It's also turning into something that I can use to help others which is amazing.
"I like to show people that you can still have a good life even while you're battling with mental health."
