But the team members did hear, as well as see, what was going on in the kitchen, because their technical ops expert, Jack Kiefer, had left a pair of Visco glasses on the kitchen counter. The frames were slightly oversized, but not absurdly so, considering the complex microelectronics embedded within. They transmitted audio and video information through a nearly microscopic microphone and lens, and the signal could be monitored up to a mile away from the glasses, without utilizing complicated, sometimes detectable signal repeaters.

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