The corridors were filled with shadows which retreated before the beams cast by our handheld lamps.

The glow of our handheld lamps didn't seem to bother them, but clearly they didn't need them to see, even in the thick darkness cast by the purple-black metal into which these tunnels had been carved.

The light withdrew a bit and, as her eyes readjusted, Ezri could make out several figures, all in Starfleet EVA suits, silhouetted in the halo of some sort of handheld lamp.

At the conclusion of the episode, Data (having been examined and repaired by Wesley and Ensign Lefler before they were forced to submit to the game) frees the rest of the crew from their mind-controlled state by flashing pulses of light in their faces from a handheld lamp.