Dark Rising: The Savage Tales of Summer Vale

Having grown up in demon dimension and enduring years of underground government training, Summer is finally back home and struggling to adjust to her new surroundings. She is recruited to head a government covert agency that, unknown to her, has its own agenda. Summer meets with a mysterious group calling themselves The Dark Shadows Club. They warn of her upcoming battle with The Dark Lord and how all of existence hangs in the balance, but not everything is what it seems.

Selected season 1, episode 1.