Doctor Who: Worlds in Time is the worlds first and only official MMORPG for Doctor Who and ran from 2011 as a free-to-play game with the goal to "become the largest Doctor Who community ever assembled." The game featured the ability to play with other Doctor Who fans amongst related adventures in a cartoon environment.
The trailer can be seen below:


Unfortunately, while it proved to be rather popular during its launch period, the game has failed to keep the interests of the fandom (probably caused by the activity limits) and has eventually decided to close, becoming just one in a long line of Doctor Who game failures, on March 3rd.

They sent the following email out to all registered members:

News in Time
We are sorry to report that Doctor Who: Worlds in Time will discontinue service on Monday, March 3rd, 2014 at noon PST.
As of today, January 14th, 2014, the game will no longer be accepting transactions from players. Existing players are welcome to use their earned in-game currency over the next two months. Customer support and game maintenance will be available through the shutdown date.
We want to thank the loyal players of Worlds in Time for supporting the game through its years of operation. The BBC has also provided the following discount code for Worlds in Time players to use in the BBC Worldwide Online Store.

• Get 10% off your order at BBCSHOP.COM

• Enter code DWAPP under ‘redeem a promotion code’ at checkout

• Offer ends 28 February 2014

• FREE UK DELIVERY

For all your Doctor Who favourites, visit BBCSHOP.COM.