Eternity Clock

The Eternity Clock was a device of unknown origins. It was split into its four components and each was sent to a different point in time. The Eleventh Doctor and River investigated the Time storm the pieces created; the pieces were crying out to each other, begging to be put back together, threatening all of reality. They were brought back together after being stolen from the Cybermen, Daleks, Silents and Silurians in different time periods. The device synched with the TARDIS and took the Doctor and River on an unknown trip. (VG: The Eternity Clock)