Animation. Dennis lives in Beanotown with Mum, Dad, little sister Bea and his pet dog Gnasher. Gnasher is more than a dog to Dennis: he is a kindred spirit. Whatever Dennis does, Gnasher does with him. Together with their friends Curly and Pie Face, Dennis and Gnasher believe the world truly is their oyster and that kids should make the rules. Not everyone agrees, including Mum and Dad, but Dennis and Gnasher are not going to let that stand in the way of their pursuit of fun! Dennis's dad takes him to the office family day, and Dennis plays pranks around the office. When Scrimp calls Dad and Dennis to his office, Dad thinks he is going to be fired because of his son's antics, but it turns out that Scrimp wants Dennis's help to invent a new line of jokes, calling them the Menace Collection. Dennis is thrilled at his new job, but when he finds out that Scrimp wants to take over Mr Har Har's joke shop, he is distraught. He works out a plan to come up with one more joke that will put Scrimp off jokes for life in order to stop him from closing down the shop. Dennis comes up with the Three In One; part whoopee cushion, part stink bomb and part space-hopper.