Mexico City is experiencing a series of child killings and through the friendship of a classmate, Lalo learns that his friend may have something that may solve these crimes, as long as the killer doesn't get to them first.

Two young men spend the night together after meeting the previous evening in a notorious gay club. The next day, however, the host wakes to find the boy he picked up bewildered and confused, unable to remember his name or anything about his past. Lacking any type of identification or obvious clues, the boys begin to search for the truth among fragments of memories that may or may not prove reliable. A chilling homoerotic thriller, BOY UNDONE is queer guerrilla filmmaking at its most intense.