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"House"-hold name: Zeljko Ivanek as Jason.
"House"-lights: Jason takes House, Thirteen and several other bystanders hostage in order to force House to diagnose his mystery illness. As the diagnosis progresses, House has to test out treatments on the hostages before Jason will agree to take them. Thirteen, having Huntington's, jeopardizes her own life by submitting to many of the treatments before they figure out Jason has Melioidosis.
Out-"House": Zeljko Ivanek can be found in all sorts of places, always playing somebody eviiiiiil ("24," "True Blood," "The Event").