Thief 4 is the fourth title in the Thief series, to be developed by Eidos Montreal. The game was confirmed on May 11, 2009, and no further information is known save a listing on Eidos home page. In early 2008, several rumors had been circulating regarding a fourth Thief game, which was allegedly under development. Eidos-Montreals General Manager Stéphane D'Astous commented in an interview for Deus Ex 3 that confirmation of the companys second AAA title, which its website states begins with the letter T, would occur over the next year or so. As of early 2010, the Thief 4 website does not provide content yet, though a link to an official forum is provided.
On May 11, 2009, the game was officially unveiled, and DAstous was quoted on the main page as stating Thief 4 was currently in early development: Were in the early development stages for Thief 4, but this is an incredibly ambitious project and a very exciting one. Its too early for us to offer any specific game details, right now we are focused on recruiting the very best talent to join the core team at the studio and help us make, what we believe will be one of the most exciting games on the market.