Sent to prison for allegedly killing her lover, Julia discovers she is pregnant and is sent to a high-security maternity ward to serve her time. Julias only concern now is her son. Her fellow inmate Marta becomes her ally; her mother Sofía, her opponent. One attempts to teach her how to be a mother; the other wishes to take over rearing the child. The film, shot in a real prison with inmates as extras, shines a light on a little known aspect of prison life: motherhood behind bars.