This short is a spin-off from "Luca" and follows one of the main characters, Alberto, in his life following the end of the previous film.
It begins with Alberto writing to his friend, Luca, who by now has gone off to school. As he writes, you see that Alberto's life with Massimo is very problematic, as Alberto knows little about human customs and he keeps making a mess of things. To make matters worse, Massimo continues to be a very quiet and reserved man and Alberto assumes the guy is getting fed up with him....particularly when he accidentally burns Massimo's boat.
I didn't love this short until the end...which was very sweet. It gave some added depth to the characters and overall, it's a very nice Pixar short.