If you wonder why the golden bed in Texas millionaire Morgan's possession is said to be the most dangerous, it's because it's guarded by laser beams, immersed in a pool of high-strength sulphuric acid, and is shielded by a tank division and numerous other systems. Lupin can't back down from stealing it because Fujiko wants it for a love nest, so, on their third assault, Lupin, Jigen, and Goemon draw off the tanks and fighter planes, and attempts to use Morgan's own 45-inch gun himself. Now, how will he fare in the end?