Doctor Will Magnus shows off his latest invention, animated toy action figures of Wonder Woman, Sgt. Rock, Enemy Ace, Captain Storm, Johnny Cloud, and the Haunted Tank. The toys are to be auctioned off, at a charity fund raiser, for the New York Association For Brain-Injured Children. That afternoon, the Metal Men appear at a party for the children. Afterwards, Magnus heads to Fire Island for some recreation. Platinum becomes jealous of the attention Magnus is giving to his model girlfriend, Cleo. In a jealous rage, Platinum attempts to drown Cleo in the ocean. Magnus orders Platinum to stop, threatening to destroy her if she doesn't comply. Spurned, Platinum races to the Metal Men's jetaway. Concerned over Platinum's emotional state, the Metal Men leap into the jetaway, before Platinum can get too far away. Platinum flies the jetaway into orbit.

The Metal Men begin receiving a distress signal, as they pull farther and farther away from Earth. Gold and Platinum mold themselves into an antenna array, to better receive the signal. By mistake, the aliens send a shrinking ray, instead of a homing beacon, to the jetaway. The Metal Men are reduced to the size of toys. Gold molds himself into a tall stack of coins, to raise the team up high enough to work the jetaway's controls. The homing beacon established, the Metal Men follow the signal to a planetoid, ringed by toy rockets. They immediately come under heavy fire. Tossed about their cabin, it's all the team can do to set the jetaway down for a safe landing. Quickly, the Metal Men discover the source of the distress signal. Two robots, carved out of wood, are being swarmed by robot termites.

The Metal Men drive the termites off, but the creatures vow to attack Earth in retaliation. The wooden robots prove to be of low intelligence. Their attempts to return the Metal Men to their proper size results in even worse physical transformations. After being knotted up like pretzels, the Metal Men abandon any hope that the Srelbmub can restore them. The Metal Men set course for Earth, in the hopes that their creator, Magnus, can return them to their normal size. In Magnus' laboratory, the Metal Men activate a device to both restore them to their normal height, and unknot them. Though the machine does straighten them out, it doesn't reverse the shrinking process. Worse, it leaves them paralyzed, and unable to speak.When the representative from the New York Association For Brain-Injured Children arrives to collect Magnus' action figures, he also takes the Metal Men, by mistake.

The Metal Men are given, as a set, to a young blind boy. When news of the robot termites' attack on Earth comes over the news, the boy weeps, wishing there were some way for him to help. The saline content of the boy's tears restores the Metal Men to their normal selves. The Metal Men travel to the termites' beachhead on Earth. Gold uses his super-conductivity to transfer enormous heat into Mercury. Transformed into fulminate of Mercury, the hot-headed Metal Man explodes, destroying both the termite invasion force, and himself, as well as the Metal Men. Magnus collects the Metal Men's remains, and sets about reconstructing them. Platinum has Magnus build real Metal Men toys, to give to the blind boy, which the Metal Men, personally, deliver.