What would you do when you go for a stroll on the beach and spot a magnificent sea creature in the shallow waters? Well, a father and his two-year-old daughter came across a beautiful octopus while they were walking on a beach in Western Australia.
Lance Karlson managed to get the experience on video, which shows the creature race through shallow water towards them at Geographe Bay.
The angry octopus approached the two and suddenly leaped out of the sea and whipped its tentacles towards Mr Karlson.
He first noticed the octopus after spotting the creature's similar attempt to attack a seagull a short time before.
Soon afterwards, Mr Karlson went for a swim and found the octopus resting among a bed of shells. However, at that point the octopus still seemed riled up and then attacked him, hitting his neck and arms with its tentacles.
"My goggles were too fogged to see what had happened and I swam back to shore in pain. The imprints of the tentacles quickly formed raised marks across my skin."
Mr Karlson, and former lifeguard, said his wife rushed to help him after the attack.
"There was some stinging but, after being a lifesaver for some years, I've been stung by bluebottles and it was not anything like that.
"It was more the pain from the physical strike of the octopus."
Since the video has been shared on his social media, a number of octopus researchers pointed out how unusual it is to see this kind of behaviour.
Octopuses, part of the cephalopod family, are considered one of the most intelligent invertebrates and rarely attack humans.
Maybe this octopus just had a blue Monday.