Time shift

A time shift was a distortion in the space-time continuum by which two time periods were linked. (TV: To the Last Man) Lifeforms with the ability to time shift were known as time-shifters. (PROSE: Lords and Masters)

St Teilo's Hospital was the location of time shifts between 1918 and the 21st century, which were investigated and ultimately neutralised by Torchwood 3 with the help of Tommy Brockless. (TV: To the Last Man)