Brütal Legend and Costume Quest developer Double Fine has unveiled The Cave, a new adventure game from Monkey Island creator Ron Gilbert.

Sega will publish the downloadable title on PC, PlayStation 3 and Xbox 360 in early 2013.

In Cave, you assemble a team of adventurers, explore a subterranean amusement park and encounter inter-continental ballistic missiles. "Rappelling", "spelunking" and dark rocky caverns also feature.

"The concept of The Cave has been bouncing around in my head for many, many years, and then the little voices that tell me to do things said it was time to make the game," Gilbert explained.

"I'm thrilled to be working with amazingly talented folks at Double Fine and ecstatic that the team at Sega believes in adventure games and quirky ideas."

Double Fine signed Gilbert to work on a new project in September 2010. He has periodically teased the game ever since.

Need to know more? Jeffrey Matulef chatted with Gilbert about the game for Eurogamer's hot-off-the-press preview of The Cave.