Dennis and Gnasher: Unleashed - Season 1 Episode 6 -

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!