Norman Boorman, a 23-year-old agora-germaphobe lives in his Uncle Happy's basement. The world is under an attack from a pandemic virus that is grinding it to a standstill. Norman has just come back from a run to the supermarket getting all the items that are scarce or hard to get because of the fear the virus has caused. Toilet paper, hand sanitizers, disinfectant sprays, paper towels and his main food staple, spaghetti noodles. He wouldn't have gone out at all, but he's on a mission for his grandmother, so he put aside his fears to take care of her and her friends.
Once inside his basement, he feels secure and protected. It's his haven from the chaos and poisons from the outside world. Norman not only has his fears, but he is OCD, so everything must be in its own place, which he goes out of his way to be sure it is. Norman is also highly intelligent in a quirky way but is a social misfit when it comes to dealing with anyone other than his grandmother and his Uncle.
Uncle Happy is a scrap dealer who comes home on his latest outing, his pickup truck filled to overflowing. Norman helps him unload and organize their half acre back yard of junk. Before anything comes off the truck Norman disinfects it. In fact, nothing comes in the house without being sprayed, including Uncle Happy.
Later that night, a UFO gets chased by another UFO, and is shot down, crashing into the large wooded area on the outskirts of Norman's hometown, Opa Locka. The injured Alien that crashed crawls out of his spaceship, through a fenced in area, marked Sewage Plant, and down into a drain field where it accesses the city's sewer system.
The next day, Uncle Happy leaves to get a load of scrap metal a days ride away, and leaves Norman in charge of everything. Norman makes Uncle Happy promise to wear all the protective gear he provides for him to stay safe from catching the virus.
In the middle of the night the injured alien makes his way through the piping system and winds up crawling into Norman's bathtub where the two soon meet and after a rocky introduction, begin to realize though they are from different galaxies they have much in common. The alien is able to recircuit a toddler toy belonging to Norman's neighbor's boy, Micah; An animal noise toy that allows them to communicate easily.
This communication leads Norman to realize the Alien is not going to hurt him, and in fact, Norman over comes his fear of the alien, and the possible germs it may carry, and he fixes and tends to the Alien's wounds. Meanwhile, the Alien, whom Norman mistakenly thinks is pronounced Pizza, reveals some amazing powers he has, such as, self-cloaking, and manipulating and controlling the things in the material world.
By the next day, the Alien has recovered quickly, thanks to Norman's doctoring him up, and introducing him to his favorite food, spaghetti, which seems to accelerate Pizza's healing process. Norman feels comfortable enough with his new guest and lets it leave his bathtub and join him for dinner. Spaghetti, of course, which was a special request of the alien. During dinner Norman learns Pizza has come to his planet, to not only deliver the cure for the virus, but has followed the alien that is responsible for unleashing the virus onto earth, with the plan to colonize it once all humans have been killed. Pizza needs to get back to his ship to release the cure into the atmosphere and stop the evil alien once and for all.
The evil alien is from a sister race of Pizza's own people. Pizza is a Fengklad, and the evil alien is a Dwengklad. They are from two planets that shared the same sun. However, the Dwengklads destroyed their own planet by using up its resources and tried to move in on Pizza's planet. The Fengklads had to create a forcefield around their planet to protect themselves which forced the Dwengklads to take over other planets throughout the galaxies, living on them, destroying them, and moving on. Now they have their sights set on Earth. Pizza's people imprisoned the Dwengklads on the last planet they were on, in an effort to keep them from leaving but they were too late to stop one of them from getting away with the virus that it has just released on earth.
Pizza asks Norman to help him, but Norman vehemently declines because of his phobias. But he suggests as soon as his Uncle gets back, he will get him to take Pizza to his ship. Then Norman receives a phone call from a hospital letting him know, Uncle Happy has contracted the virus and they do not know how long he will live. With this news, Norman has no choice but to overcome his fears, help Pizza get to his ship, spread the cure, and stop the evil alien to save his uncle and the planet.
To do that, they must outrun the police who are enforcing a state wide lockdown, overcome the Dwengklad alien who attacks them and defeats Pizza, and when all seems lost, and the evil alien leaves Norman for dead, they take one last chance ultimately beating the evil alien with a surprise attack. Then they use the evil alien's ship to spread the cure and save Uncle Happy and the planet.
There's An Alien In My Bathtub is a quirky science fiction comedy, with a timely backdrop of a world-wide pandemic that's perfect for the whole family. It's a buddy movie that reaches across the galaxies with heart and laughter.