"The Hawking Excitation" is the 21st episode of the fifth season of The Big Bang Theory that first aired on CBS on April 5, 2012. It is the 108th episode overall. After learning that Stephen Hawking is coming to lecture at Caltech, Howard (Simon Helberg) is hired to maintain his wheelchair equipment. When Sheldon (Jim Parsons) discovers this, he is desperate to meet Hawking. Howard says he can, but only if he completes a humiliating series of tasks.