Max, Michael, Isabel, & Tess. 4 teenage human/alien hybrids living in Roswell, New Mexico. When their secret is exposed to save Liz, a human girl's life, they know she must be told the truth. Liz's friends Maria, Alex, & Kyle all find out & when everyone's life is put in danger, they are now all aware that this is much more dangerous than keeping the aliens safe, but that everyone is now involved.