After reluctantly returning to her tourist-trap hometown of Roswell, New Mexico, the daughter of undocumented immigrants discovers a shocking truth about her teenage crush who is now a police officer: he's an alien who has kept his unearthly abilities hidden his entire life. She protects his secret as the two reconnect and begin to investigate his origins, but when a violent attack and long-standing government cover-up point to a greater alien presence on Earth, the politics of fear and hatred threaten to expose him and destroy their deepening romance.