Faith (Dead Man Walking)
Faith was a young girl who lived in 15th century Cardiff who brought Death into the real world through the Resurrection gauntlet. In the end she managed to send Death back before he could claim 13 lives. (TW:Dead Man Walking)
It is rumoured that the Young Girl, a tarot card reader and possible friend of Jack Harkness, is Faith, as she hasn't aged from the first time she and Harkness met (TW:Fragments) in the late 19th century and when he asked for the location of the second Resurrection gauntlet(TW:Dead Man Walking)in 2008, suggesting that she may be immortal like Torchwood 3 member Owen Harper, also a Reserrection gauntlet 'victim'.