isterjaw was a shark. A sleek predator of the deep that is master of its habitat; menacing, unpredictable and not to be trifled with. True to the nature of his kind, Misterjaw took the greatest pleasure in sneaking up on unsuspecting victims and yelling, "Gotcha!" while baring his teeth and making a show of lethality. The top hat and tuxedo vest wearing shark, however, was content to merely scare humans. That was not the case with Harry Halibut though, a tasty morsel of a fish that was constantly on the run (or rather, swim) from Misterjaw. Luckily for the little fellow, Misterjaw couldn't resist yelling 'gotcha' before attempting to dine, which gave the halibut enough warning to escape (although all the 'gotchas' couldn't have done his heart much good).

Every big shot needs a lackey, and Misterjaw had his - a bootlicking, ego booster called Catfish, who accompanied Misterjaw everywhere and was always ready to throw Misterjaw (who he referred to as "Boss" or "Chief") a compliment. He was also there to take the blame when something went wrong. Misterjaw had a slew of names for Catfish when he got upset, such as "nitwit," "knucklehead" or "dummy." If he was particularly upset he'd threaten to give Catfish a 'gotcha,' which never ceased to intimidate Catfish because he knew what a good 'gotcha' could do.

Among other adventures, Misterjaw was occasionally confronted with a shark hunter called Fearless Freddy. Freddy wasn't fearless, but he did show more nerve when it came to sharks than most people would. Unfortunately for Fearless Freddy, he was always one step behind Misterjaw, who saw the shark hunter's pursuit as just another opportunity to get in some good scares.