Alien: Isolation around 15 hours long

Upcoming survival horror title Alien: Isolation will be "close to 15 hours" long, according to lead designer Gary Napper.

Napper revealed the details to PlayStation Access, saying the original music score has had to be re-recorded.

"We've re-recorded large portions of the original score because obviously the film is only a couple of hours long," he said.

"Our game is close to 15 hours, really, so we need a lot of different music for a lot of different situations."

Napper also explained the enemy AI in Isolation, and what players can expect to find.

"[The Alien] takes things into account like whether it's seen you before, if it recognises you, we match that against the gameplay because very early we found we'd made this perfect killer, and if it found you every time and killed you there wasn't much gameplay there.

"So we do things like, when it first sees you it turns and hisses, and if it hasn't seen you before it tries to make out what you are. If you're quick to go away then it'll just search over where you've been and we extrapolate that out for the rest of the game and the other mechanics."

Alien: Isolation releases 7 October.