The first full length trailer for Ryan Murphy's 'Scream Queens' reveals a handful of new characters and a mystery 20 years in the making.

The 15-episode first season focuses on a college campus with a pesky murder problem. Emma Roberts stars as Chanel Oberlin, the head of Kappa House who’s displeased that Dean Munsch (Jamie Lee Curtis) has decreed that her sorority must be open to all students at Wallace University, not just the well-off upper class. However, as soon as that happens, a serial killer dressed like a devil begins to haunt their halls, picking off one student at a time — and everyone is a suspect.

Joe Manganiello, Lea Michele, Abigail Breslin, Keke Palmer, Ariana Grande and Nick Jonas also star in the horror comedy from Murphy, Brad Falchuk and Ian Brennan, the creators of "Glee" and "American Horror Story."

"Scream Queens" will air this fall on Fox.