This defense-minded episode concerns Dr. J's dual role as a physics teacher and a part-time CIA agent. The United States (represented by Dr. J) and Russia were both working on a real-life nuclear-powered limb (á la Steve Austin) to be used by government spies who might have lost or damaged their arms in some way. (You guessed it - this is the famous nuclear arms race.) Finally, both countries finished limbs and fitted them to suitable subjects. The Russians tested theirs by having their agent (Big Fist) throw a ball weighing 490 N straight up into the air. They measured the initial acceleration of the ball to be 100 m/sec². Dr. J decided to test his limb in a different manner. He had his agent push a large safe across the street. In order to push the safe (which weighed 5000 N), he had to overcome a force of friction of 3500 N. In addition, members of SAP (being against any type of physics) decided to push against the safe opposite to the bionic subject with a force of 500 N. The bionic subject still managed to accelerate the safe forward.