Army of Darkness
In this sequel to the Evil Dead films Ash is time-warped to a medieval castle beset by monstrous forces, including a possessed witch (Patricia Tallman). Initially mistaken for an enemy he is soon revealed as the prophesied savior who can quest for the Necronomicon, a book which can dispel the evil.
He also falls for a woman named Sheila (Embeth Davidtz) and seeks to impress her. Unfortunately he screws up the magic words while collecting the tome and releases an army of skeletons led by his own Deadite counterpart and a Deadite Sheila.
Ash has to rely on twentieth-Century tactics and his trusty shotgun to defeat the minions of darkness, save the world, and return home.