Story details and concept art from Bungie’s upcoming space game Destiny have hit the Internet.

The leaked materials were prepared by an advertising agency and wound up in the hands of IGN.

“Our story begins seven hundred years from now in the Last City on Earth, in a Solar System littered with the ruins of man’s Golden Age,” reads the document.

“A massive, mysterious alien ship hangs overhead like a second Moon. No one knows where it came from or what it’s here for, but only that it’s our protector. Meanwhile, strange, alien monsters creep in from the edge of the universe, determined to take Earth and the Last City.

“We are young ‘knights’ tasked with defending the remains of humanity, discovering the source of these monsters and – eventually – overcoming it.”

The massive alien ship is also referred to as “the Traveler”.

According to the document, Bungie is seeking to make Destiny “fun and accessible to all”, and wants “to create a universe as deep, tangible and relatable as that of the Star Wars franchise”, with gameplay that is “social at its core”.

“Destiny is designed for your inner seven year old. We want to make it feel like a mythic adventure,” reads a quote from Bungie co-founder Jason Jones.

Contacted over the leak, Bungie released the following statement:

“We’re not quite ready to take the wraps off our next universe, but in light of recent events we thought we’d give fans something a little more official over at Bungie.net. Feel free to drop by and say hello! There’s much more to come.”

Details around the ambitious Destiny project first emerged in May, when the game's contract between Activision and Bungie emerged via the Activision/Infinity Ward Call of Duty court case.

That contract outlined the release schedule for Destiny and offshoot Comet, which it stated would be released in an annual alternating fashion from 2013 to 2020.