Jake was once piloting his space craft when he was forced to make an emergency landing on Earth. When the Army takes his space ship into custody, Jake realizes that he needs help to not only get his ship back, but repair it as well, since the Mother Ship cannot send a rescue vessel in time. Tracking the military to the Energy Research Laboratory (E.R.L.) Jake uses his special collar to spy on the top energy specialists in the country, hoping to find an ally. While none of them possesses the knowledge that Jake needs, a theoretical scientist named Dr. Frank Wilson catches Jake's attention when he explains that the propulsion unit from Jake's ship, which the military had brought only wishing to learn it's what makes it tick, is tapping the Primal Mainstream. More commonly referred to as electromagnetic energy pulled in from the universe itself. Frank is rebuffed in his claims due to his odd sense of humor but Jake sees he has potential.
Jake follows Frank to his office in the bottom floor of the E.R.L. building, where Frank nicknames him Jake. Before Jake can communicate with Frank his intentions, Dr. Liz Bartlet interrupts them and scolds Frank for his lighthearted attitude while Jake observes. Frank calms her, mostly by introducing Jake himself. Once she's gone, Jake reveals his true nature to Frank.
Jake explains to Frank that he's been separated from the mother ship, and will need some help to return home. The extraterrestrial cat reveals some of his powers to Frank; such as levitation. With Jake's help and the use of a spare collar, an impossibility like flight becomes reality for Frank.
Soon others join in the effort to help Jake return home. First Dr. Link, a man whose interest in gambling becomes very useful. As well as Liz, who also has a photogenic cat, Lucybelle once she's told the truth of the situation.
Jake needs $120,000 worth of gold to get his spaceship back into orbit, so the group of doctors face a challenge. So Jake embraces gambling to raise the money to buy the required gold. Sadly, Jake is knocked unconscious and his new human friends wind up at a poolhall, where they at first try to use Jake's collar themselves, with disastrous results. Fortunately Jake wakes up in time to help Liz win enough money during her game.
Meanwhile, the U.S. military are on their trail, Jake treats some of them to a standstill treatment, allowing himself and Frank the chance to get onto the base and repair his ship before the deadline.
However, all this time, a man named Stallwood, has been watching Jake and Frank. Working as a spy at E.R.L. Worse still, Stallwood works for a master criminal calling himself Mr. Olympus, who is after the secret of Jake's collar for the purposes of universal domination. To make matters worse, the military are also on to Jake and Frank's trail, and go to arrest them for the sake of National Security.
Jake and Frank manage to elude the military and the criminals, only to have Link and Liz (as well as Lucybelle) captured by Mr. Olympus. They plan to ransom them back for the collar, which forces Jake to make a desperate decision. Jake sends his ship back to the awaiting Mother Ship, which will not return for another 115 years, and makes the decision to stay on Earth in order to help rescue his new friends.
In the end, Jake and Frank use a broken-down biplane to rescue Liz and Lucybelle from Mr. Olympus, and Jake is allowed to stay as a representative of a 'friendly power'.
Jake later applies for citizenship in the United States, with Frank as his sponsor, using his powers to levitate the judge who is swearing him in.
While Jake often points out how far behind humans are compared to his own species in technology and science, Jake does not think himself better than humans.