"One," says Douglas MacArthur Shaftoe, "to provide power to the ROV. But this ROV carries its own power source-an oxygen/natural gas swash-plate motor, adapted from torpedo technology, and part of our peace dividend " (that is the other thing Randy likes about military people—their mastery of deadpan humor) "that generates enough electricity to run all of the thrusters. Two, for communications and control. But this unit uses blue-green lasers to communicate with the control console which Amy is manning. Three, for emergency recovery in the event of total systems failure. But if this unit fails, it is smart enough, supposedly, to inflate a bladder and float up to the surface where it will activate a strobe light so that we can go recover it."