1UP- Much like last year's inFamous: Festival of Blood, American Nightmare occupies the "stand-alone downloadable expansion thing" category. Like Festival, its premise hinges on the main character's sidekick. Festival had Zeke tell a tall tale about Cole turning into a vampire in order to get a woman to come home with him, whereas Nightmare starts with Alan's former agent Barry Wheeler falling asleep in a motel while the camera zooms in on the episode of Night Springs (the Twilight Zone analog in Alan's universe) playing in the background. Nightmare puts Alan inside that episode of Night Springs, and it sees him investigating the Arizona town and helping three damsels-in-distress, all while pursuing Mr. Scratch.
The gameplay loop works just like a slightly tweaked version of Alan Wake, which itself played like Remedy's previous character-centric third-person game Max Payne: You split your time between shooting and a gameplay mechanic that complements said shooting, which in Wake's case is shining light on enemies. Whether you're an Alan Wake veteran or someone who's never played it, you should be able to pick up Nightmare's gameplay pretty damn easily.