Evan Petkau and Luke Willms, a couple of average dudes from Vancouver, Canada, were on a tour of Lake Naivasha in Kenya when their boat was suddenly accosted by a pod of angry hippopotami.

When hippos aren't acting out their roles as the poofy, adorable creatures of popular lore, they're vicious, boat-chasing monsters. Check out this news video from MSNBC, in which a very angry-looking hippo head rises out of the water to chase down Petkau and Willms.