A small spaceship resembling a human is sent to Earth with a crew of tiny alien beings inside it. These aliens, led by their captain, have arrived to save their home planet, Nil, which relies on salt to survive. Disguised as a human named Dave, the spaceship begins searching for a way to extract the ocean's salt without alerting Earth's inhabitants. The aliens must adapt to human behavior and customs without drawing too much attention. "Dave" encounters Gina Morrison, a single mother who helps him learn more about human emotions and establish a connection with her and her young son.

As the mission progresses, the crew inside "Dave" faces unexpected challenges and dilemmas. They must decide between pursuing their planet-saving directive or embracing the newfound empathy and relationships they have developed on Earth. The captain and his crew become increasingly conflicted as they learn more about human beings and the potential consequences of their actions. Their experiences force them to reevaluate their priorities, leading to choices that will impact both their home planet and the lives of the humans they have come to care about.