Clyde Langer

Clyde Langer was a class mate of Maria Jackson and Luke Smith. He met Maria and Luke on his first day of high school. He disliked the school dinners as the food was rotten due to a Slitheen machine in the school. The next day he brought a home made chip sandwich to school where the science teacher, a Slitheen in disguise, had a negative reaction to the vinegar in the sandwich as vinegar is the Raxacoricofallapatorian's weakness. After school his science teacher unmasked and chased Maria and Clyde, Clyde sprayed deodorant to confuse the advanced sense of smell of the Raxacoricofallapatorian. After meeting Sarah Jane Smith he helped defeat the Slitheen. (SJA: Revenge of the Slitheen)

His grandmother, who knew Mrs. Randall who lived at Lavender Lawns, tipped him off that there was something strange happening there. The claimed she made were in fact true as the manager, Mrs. Gribbins, was in league with a Gorgon. (SJA: Eye of the Gorgon) He and Luke went to laser tag centre where he and Luke were telported to General Kudlak's battle station. There he met others kids who had gone missing due to winning the laser tag. He was helped to get home safely with the help of Sarah Jane. (SJA: Warriors of Kudlak)

If Donna had turned right
Because Donna Noble turned right to go on to another job interview, time was changed resulting in a chaged timeline. Clyde went to The Royal Hope hospital with Sarah Jane, Maria and Luke only to find that he had been telepored to the moon. Because every one had ran out of Oxyegen he suffacted along with every one in the Hospital. (DW: Turn Left)