Emily Webb has always felt left out. The other Emily at school is popular and pretty. Until one night she's found murdered. No one knows who did it, just that there's a killer on the loose. Emily Webb goes through changes at night. She can't explain it, doesn't know what it's from. But as her "nighttime" Emily, she has confidence, speed, and power. Something that the daytime Emily does not. As she goes through her changes, she realizes the killer is targeting her kind.