Liz Ortecho is a jaded biomedical researcher who has recently returned to her hometown of Roswell to care for her ill father after being away for over 10 years.
Her arrival allows her to reconnect with her high school crush Max Evans, who now works as a police officer. But Liz is surprised to learn that Max and his siblings are aliens who have spent their lives hiding their otherworldly abilities.
As Liz grows closer to Max, it gets harder for her to keep the truth from her other friends. But concealing the siblings' true identities is crucial, as a long-running government conspiracy and the politics of fear and hatred put their lives at risk.