As they sit on the train, Milo begins making up stories about all of the people on the train around them. He loves using his imagination to draw. They sit next to a passenger who is crying. Milo turns his attention to the “Debbie Downer” that they are seated next to, and imagines why they are so sad. Debbie Downer sings about how they have had a horrible day and lost their pet bird. Suddenly we are brought back to the real world and Debbie Downer gets off the subway.

At this train stop, a “Super Cool Guy” sits next to Adrienne and begins to flirt with her. Milo quickly interrupts the moment by showing the guy a drawing of him being eaten by a Hippo, and the super cool guy leaves. Adrienne sings about how much Milo annoys her and how hard it is to be in charge of him sometimes.

At the next stop, a group of breakdancers perform an awesome performance about following their dreams on the subway. Milo starts drawing their life and envisions the breakdancer dancing and performing different places. Suddenly the dancer is told to stop performing on the sidewalk and the police are threatened to be called.

As we shift back to reality, the pair is going into a scary tunnel of the subway system. The subway stops momentarily and Milo remembers the things his mom taught him when things get scary: to focus on other things like his super cool hat and wait for the moment to pass. Milo sees a boy his age, Kevin, that looks super cool and important, and envisions his life as a King with a horse-drawn carriage, castle, and servants. Milo is pulled back to reality and reflects on his own life, how he sees himself, and how others might see him.

Milo is so deep in thought that he and Adrienne miss their next subway connection. In her frustration and stress, Adrienne accidentally damages Milo’s drawing for their mom. Feelings hurt, Milo runs away into the crowded city streets. Adrienne races through the city to find Milo, who is by himself in the train station. Adrienne appears, apologizes to Milo, and they make up before getting on the next train. While discussing the drawing, Milo reveals that the Superwoman character in his drawing is their mom, “Supermom.”

The siblings finally get off the train at their destination, a visiting room at a prison. Milo sees Kevin, the same little boy he thought was a king, in the visiting room. Milo realizes that maybe the way people look on the outside is not always completely true and that everyone has unique stories. The different characters from before reveal their truths, Debbie Downer has allergies, the Breakdancer is a Broadway star, and Kevin is also visiting a parent in prison.

Their mom greets the kids. The family hugs each other and discusses their past week since seeing one another. Milo shows them the drawing he made. It is not of Supermom or any attacking creatures, but instead, the three of them eating ice cream on a Sunday afternoon. The family mimes eating ice cream cones, laughs, and then says goodbye. They promise to keep visiting until Mom is back home, and the siblings get back on the train home.