Eidos Interactive, today announced an agreement with Microsoft to release two brand new downloadable chapters in the continuing Tomb Raider adventures of Lara Croft. Containing up to six hours of new gameplay and content for Tomb Raider: Underworld, the chapters will be available exclusively on Xbox LIVE Marketplace for the Xbox 360. A demo for Tomb Raider: Underworld will also be available on Xbox Live Marketplace in October.

Offering entirely new content specifically designed to extend the Tomb Raider: Underworld experience, Tomb Raider: Underworld – Beneath the Ashes and Tomb Raider: Underworld – Lara’s Shadow will deliver two very different single player gameplay experiences. Tomb Raider: Underworld – Beneath the Ashes takes place after the Underworld story has finished and will feature an incredible new environment to explore, additional secrets to unlock and different enemies to fight. Tomb Raider: Underworld - Lara’s Shadow will introduce players to a new kind of playable character and create a unique Tomb Raider experience.

The first new chapter, Tomb Raider: Underworld – Beneath the Ashes, will be available for download exclusively on Xbox Live Marketplace this Christmas. Tomb Raider: Underworld – Lara’s Shadow will follow in early 2009.

“We are constantly looking at ways to extend our franchises, whilst developing a deeper relationship with our players. The retail release of any videogame is just the start of the player experience, from there it all depends where you want to take the player in terms of ideas and innovation,” said Sean Vesce. “With these additional chapters and the online reach of Xbox Live, we are able to deliver exclusive content to millions of gamers worldwide.”

“We’re thrilled that Xbox owners will be able to extend their Lara Croft adventures with exclusive ‘Tomb Raider: Underworld’ episodes,” said George Peckham, General Manager of Global Third Party Publishing for Microsoft’s Interactive Entertainment Business. “We look forward to continue working closely with our great publishing partners to deliver the most robust gaming experiences, only on Xbox 360.”