Let's get this out of the way: Yes, the premise of this week's House–and apparently next week's season finale–isn't too far removed from the Season Two finale "No Reason," in which almost the entire episode turned out to be a hallucination. But this week's had a few good twists to set it apart. "House's Head" begins shortly after a bus wreck that's left House's memory cloudy about what he was doing on the bus in the first place. With the help of drugs, hypnotism and a throbbing concussion, House is able to project himself back onto the bus, where he converses with the other passengers and bounces ideas off his friends and colleagues–or at least how he imagines his friends and colleagues.
Why does House need to remember the events on the bus? Because he's convinced that before the crash, he spotted a potential patient among the passengers–only he can't remember which one, or what the symptoms were. He narrows it down to the driver, who does seem to have a tricky array of SUS, but every time House descends back into his subconscious, he's haunted by faces and visions that don't fit into the puzzle.
I really enjoyed watching House fumble to come up with a diagnosis without any of the important clues–it was sort of like the medical version of Sudoku–but I feel a bit hesitant reviewing this episode, because the story's incomplete, and given its big final twist, this is one story that's going to have to play out before I can decide whether it really works or not.
The twist: The real POW House spotted on the bus was none other than Amber (a.k.a. "Cutthroat Bitch," ak.a. the last person that House should be cannoodling with if he values Wilson's friendship). And though the crash left Amber with a bad case of pole-leg, House is convinced–judging by the teaser for the finale–that she was in trouble long before the crash occurred.