Clyde Langer is a class mate of Maria Jackson and Luke Smith he made his first appearence in Revenge of the Slitheen. On his first day of high school he met Maria and Luke and disliked the school dinners finding out of date food. The next day he brought a home made sandwhich in and the science teacher did not like this and had a reaction. This was because his science teacher was a Raxafalibtorian. After school his science teacher unmasked and chased Luke and he bumped into Clyde, Clyde sprayed deoderant and the Slitheen went away. After meeting Sarah Jane Smith he helped defeat the Slitheen.