House wakes in a strip club covered in blood with four hours of memory missing and a fractured skull, while outside, the bus he was riding has crashed. With his short-term memory compromised by temporal lobe edema, he can only tell his team that he witnessed a symptom in an unidentified passenger before the crash — someone he believes is dying. The team works the bus driver as a surrogate patient through paralysis, liver failure, and respiratory failure, while House pursues the memory through hypnosis, hallucination, and a full bus re-enactment before injecting a cardiac-risk drug to force recall. His heart stops.

The episode reframes the medical mystery as a memory problem: the unreliable witness and the only witness are the same person. It also plants the revelation that Amber Volakis — Wilson's girlfriend — has been the figure House's su ...