In Torchwood (the series), Captain Jack Harkness gives some information on how he became immortal and what it means to him. This may be considered spoily to people who haven't seen Torchwood yet.

He says he's waiting for a doctor to 'cure' him. He says something happend to him long ago that made him unable to die.

Is that answered anywhere in the Doctor Who or Torchwood series?


5 Answers 5


In the 9th Doctor episode The Parting of the Ways,

Jack was killed (exterminated!) defending Satellite 5 against a Dalek invasion fleet.

After this,

Jack was resurrected by Rose (who had the powers of the Time Vortex at this point).

Although we know that he survived at that stage, we don't know that he cannot be killed (this is revealed in later episodes), but it's presumably the cause. This was probably an accident caused by inexperience and wielding powers that are not meant to be used.

  • 2
    There's probably a bit of Timey-Wimey Ball physics at work, but also worth noting that Jack in Torchwood is repeatedly referred to as a "fixed point", which is used in Who to denote events that can't or aren't allowed to be changed. It doesn't make a lot of sense, since the phrase refers to events and not things, but one could reasonably speculate that this particular... resolution, was accomplished by making some distant part of his future one of these "fixed points". It's consistent with the Whoniverse; if a person is involved in a FP then they can't (permanently) die beforehand.
    – Aaronaught
    Commented Aug 29, 2011 at 23:17
  • 3
    As pointed out in the answer, the "fixed point" bit stems from (see: spoiler)'s misuse of the power they had, not realizing exactly what they were creating by trying to "fix" things. Thus it's not exactly the same as a fixed point in time, more of a "statis condition" -- the condition Jack was in when (spoiler) happened is now fixed for him, and any changes from that condition are quickly "rolled back". Doesn't explain the Face of Boe tho :\
    – KutuluMike
    Commented May 29, 2012 at 16:06
  • I think "fixed point" describes a timeline that can no longer be changed by time travel. Applied to an event, it means the timeline must always evolve from that point. Applied to Harkness, doesn't mean his immortality stems from a "rollback", but that the timeline of his life can not be altered by time travellers (conundrum: he himself travels in time a lot). So, doesn't conflict with the apparent multi-billion year evolution into the Face of Boe.
    – Anthony X
    Commented Sep 1, 2014 at 15:03

In addition to Tony's answer, more information about Jack's immortality is given in the Doctor Who season 3 episode Utopia, where Jack finally catches up with the Doctor again and they are transported to the year 100 trillion (!). In that episode

Jack talks about being filled with the Time Vortex and being brought back to life, and how he gradually discovered he could not be killed. The Doctor in turn reveals that he considers Jack's immortal status to be unnatural, which is why he'd been avoiding him ever since.

At the end of the following episode, Last of the Time Lords, it's hinted that...

Jack eventually becomes the Face of Boe.


Just thought I would throw my 2 cents in. He’s not immortal, he just ages super super super super-slow.

In the season 3 episode “Last of the Time Lords”, Jack says when he was a Time Agent he used to be called “the Face of Boe”, so we know he does die in the earlier season 3 episode "Gridlock".

Please see this link for the clip:

So to end, he’s not immortal per se, he is just super and filled with time vortex.

  • 1
    What would you call someone who near-instantly recovers from death, if not "immortal"?
    – Adeptus
    Commented May 20, 2016 at 5:00
  • Damn dude, that really needs a spoiler.
    – Prometheus
    Commented May 24, 2017 at 3:51

Captain Jack Harkness became immortal in season 1 on Doctor Who (2005) in the last episode. He died and resurrected thanks to Rose.

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    Coming in a year late and giving an answer that just repeats the first answer. Bad form. Commented May 28, 2012 at 17:50

Jack was contaminated with the nano genes during his first two appearances. Thus when he dies they resurrect him back to that version. The fact that it is not instantaneous means it is not a time vortex phenomena as well as the fact that he is always the same. The incident with Rose and the time vortex was coincidental and may have confused the Doctor or the Doctor may simply be lying. Spoiler: The Character Nancy was also exposed to the nano genes when they examined her and determined her DNA and the DNA of her child was the pattern they should use for humans. Nancy can not die as well, and each time she is killed she returns in a 21 year old body of a woman. Now she has returned to the episodes and has finally found the doctor again.

  • 1
    What nano-genes?
    – Suman Roy
    Commented Aug 14, 2014 at 9:04
  • @SumanRoy The nanogenes were first seen in The Empty Child. That is also the first appearance of Jack Harness, and he does use them. However, the answer given is completely wrong.
    – user137369
    Commented Nov 4, 2015 at 13:52
  • Uhh...I honestly don't know how to respond to this answer. It's so wrong in so many ways that it kinda makes sense within it's own context. WOW
    – Suman Roy
    Commented Nov 12, 2015 at 5:58

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