A mugging victim arrives at Princeton-Plainsboro with no ID and no memory of who he is — and begins mirroring the identity, complaints, and personality of whoever dominates the room. House diagnoses Giovannini Mirror Syndrome, but treating the patient requires first understanding him, which means the fellowship candidates must spend time alone with someone who reflects them back with uncomfortable accuracy. The case breaks when a contradiction in the mirroring reveals the patient has some independent thought, and House exploits that to extract a life history that points to eperythrozoon from pig farm exposure. Running parallel to the medicine: Foreman returns as House's official overseer after his outside job collapses, and the episode turns on who actually holds authority in that department.

This episode reframes the mirror as a diagnostic ...