Update: All codes should work now. We redeemed Crew Expendable as of 6:55PM ET.
The best reason to have pre-ordered Alien: Isolation is to receive Crew Expendable, an exclusive mission starring the cast of the 1979 Alien film, including Sigourney Weaver as hero Ellen Ripley.
Copies of Alien: Isolation Nostromo Edition come with inserts featuring the code, which you redeem by visiting your digital store of choice. Unfortunately, it appears codes for the PlayStation 4 version don't work.
At first we thought it was just our copies of the game, but we soon discovered other Alien fans expressing their frustrations on message boards. We can't rule out bad codes just yet, but odds are good that Sega, Sony or whoever's in charge of making the Crew Expendable DLC available simply has not done it yet, and will at some point throughout the day. For now, we'll play the game until receiving the green light.
No word on the Xbox versions of Isolation. Let us know if you run into any issues. We'll update when it goes live.
In the meantime, check out Prima's free Alien: Isolation walkthrough.