Underwater LED light

An underwater light, e.g., for a pool or spa, includes an ordinarily watertight housing, an outer compartment within the housing and floodable by water flowing therein in the event the housing is no longer watertight, a current shield within the outer compartment and at least partially defining an inner compartment within the outer compartment, a light emitter within the inner compartment, a passageway communicating between the inner and outer compartments such that outer compartment flood water can enter the inner compartment and contact the light emitter, and a conductor. The conductor is positioned so as to collect stray electrical current conducted from the inner compartment by water within the passageway, thereby reducing the risk of shock presented by such stray electrical current. The underwater light is installable within a wet niche, and includes a transformer housed in a separate compartment that extends into the wet niche for thorough cooling thereof.