South Park Episode 813 - "Cartman's Incredible Gift"

After sustaining a severe head injury, Cartman appears to have the power to see into the future.

South Park detectives are quick to enlist his help in cracking unsolved murder cases and Cartman is more than willing to help, for a price. In the meantime, a group of “licensed” psychics cry foul when Cartman refuses to join their ranks.