Dennis' ultimate hero, Grizzly Griller, plans on trekking to the source of the River Beano, broadcasting the treacherous path on live TV. Dennis introduces him to his pet hamster, Galahad - only to discover they are his biggest fear! Grizzly is so afraid that Dennis must disguise himself as his hero and go in his place!
Series 1: 38. Bertie's Backbone
Dennis and the gang train Bertie in the art of standing up to people so he can rebel against Walter's bossiness - but they train him too well and he becomes a dangerous reb ...