He is a gray buff shark that wears an olive green shirt, olive green pants and brown shoes.
Roderick's personality is that of a stereotypical drill sergant who is very serious about his job.
He replaces Mrs. Puff after she is fired from her position as Driving Instructor, due to SpongeBob failing another driving test. While teaching SpongeBob, Roderick's strict training technique of forcing SpongeBob complete the course blind-folded allows SpongeBob to drive perfectly. However, when SpongeBob begins his official driving test, Sam doesn't allow SpongeBob to wear a blindfold, despite SpongeBob's training only being done with one. SpongeBob then reverts back to his old ways, rampaging across the city. Roderick, in an attempt to stop the dangerous driving of SpongeBob, sacrifices himself to stop the boat, stating that he wants Gunther to tell his wife that he loves her. His attempt was unsucessful, and he was hit by the boat, with his fate remaining unknown. His name was never said in the episode.
Even though Sam is a Sergeant, the insignia on his shoulder shows that he is a Corporal.