A 24 hour period in the lives of Fausto and Jesus, two undocumented Mexican day-laborers in L.A. Each day another task, each day the same pressure to find money. They go about their daily routine, standing on the corner at the Home Improvement Store waiting for work to come. Today, the job they are given is well paid compared to their poor usual wages. Today, Jesus carries a shotgun inside his backpack.

A young man is confined in a mental hospital. Through a flashback we see that he was traumatized as a child, when he and his family were circus performers: he saw his father cut off the arms of his mother, a religious fanatic and leader of the heretical church of Santa Sangre ("Holy Blood"), and then commit suicide. Back in the present, he escapes and rejoins his surviving and armless mother. Against his will, he "becomes her arms" and the two undertake a grisly campaign of murder and revenge.

A professional killer comes out ot retirement to investigate and avenge the brutal murder of an old friend.