River Song put her life energy, expended "all of her regenerations" into the 12th Doctor in "Let's Kill Hitler", and it was utilized - it saved his life.

Gallifreyan physiology and technology only allowed 12 regenerations before the episode "Time of the Doctor".

He meets old versions of his previous regenerations in "Day of the Doctor" implying that he gets to "revisit old favorites".

In the "Time of the Doctor" the pocket-universe Gallifrey gives the Doctor a regeneration energy that gives him a 13th regeneration AND regenerates his unused time in previous regenerations is put into the Doctor. He doesn't just get number 13. He gets 13-24 (or really 1-12 part 2). And here is where the question comes in.

The Doctor had expended his 12 regenerations in regenerating himself previous to Day of the doctor, but that is not all that he had done with them. Somehow those expenses were "recovered". Some of his own regeneration energy had been put in other places.

Now he had expended previous regeneration energy into River Song. He puts regeneration energy into River in "The angels take Manhattan". There are several places where his regeneration is used in alternate and potentially interesting ways. Rose, Donna, the Hand.

The Question:

In him was more than his own regeneration energy. River Song put her life energy, expended "all of her regenerations" into the 12th Doctor in "Let's kill Hitler", and it was utilized - it saved his life.

He was dead, and in order to be alive required all of River Songs regenerations. The energy that restored the lost regenerations to the doctor, can it apply to her?

One might even be able to argue that they regenerated her regenerations and not his. Could River song have her lives given back or even enhanced due to what Gallifrey did in "Time of the Doctor"?

Speculation (hopefully appropriate in Sci-fi).

When he entered his own time-stream to rescue his impossible girl, the "dead" river song hologram/ghost mentioned "spoilers" - perhaps she isn't dead, and perhaps a regeneration would allow her to exit the library hologram system.

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    “the pocket-universe Gallifrey gives the Doctor a regeneration energy that gives him a 13th regeneration AND regenerates his unused time in previous regenerations is put into the Doctor” — eh? When is “unused time in previous regenerations” mentioned? – Paul D. Waite Feb 2 '15 at 17:28
  • "Day of the Doctor" - revisiting a few favorites. While its cause is not stated, the surety of the consequence is established. The implication in "Time of the Doctor" is that the "12 regenerations limit" is overcome by what happened. The proximity in time, title, and subseries really suggest stronger than normal connections between the three "... of the doctor" episodes. – EngrStudent Feb 2 '15 at 17:51
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    I’m not sure I understand what you’re saying. Do you mean that when Tom Baker says “in years to come, you might find yourself revisiting a few. But just the old favourites, eh?” in Day of the Doctor, he means that unused time from previous regenerations will be used to give the Doctor more regenerations in Time of the Doctor? (If so, have a sit down old chap, because you appear to be rambling incoherently.) – Paul D. Waite Feb 2 '15 at 20:05
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    @EngrStudent I still have a feeling that you are seriously misunderstanding how the extra regenerations work. They had nothing at all to do with his past lives or unused previous regenerations. The Time Lords simply gave him more. This is well-established "canon", mentioned as far back as The Five Doctors, that they could do that whenever they wanted. – KutuluMike Feb 2 '15 at 22:04
  • @MichaelEdenfield - you may be right. My primary exposure except for young childhood exposure, is the extent of Dr. Who available on NetFlix. – EngrStudent Feb 2 '15 at 23:49

I"m not sure what you mean by "regenerates his unused time in previous regenerations", so I can't really comment on that part, but for the rest of your question:

tl;dr: She could have been given more regenerations, if she were still alive, but it would have had nothing to do with The Doctor.

In "Let's Kill Hitler", River uses up all of her remaining regenerations to heal The Doctor. Note that this only appears to be possible because she was still in the middle of her (2nd?) regeneration cycle, and we've seen several cases where regeneration energy can be diverted during that process. But, the key take away from that scene is, The Doctor did not get any new regenerations from River. He merely got to use her energy to heal himself. He was on last last regeneration before River saved him, and he was on his last regeneration after she finished.

Thus, it doesn't seem likely that a Time Lord can "give away" their own regenerations to another Time Lord, so The Doctor having a bunch of new regenerations wouldn't help River at all. (There is some evidence that they can be "stolen", but that may also just be a crazy idea in The Master's head.)

However, there is a way for a Time Lord to get more regenerations, and we've seen it more than once: The Council of Time Lords can give them out. This has nothing to do with restoring old regeneration energy or anything like that. The 12-regeneration limit, however it came about, is simply not a hard-and-fast limit. Any time they want to, the Council of Time Lords can simply give a Time Lord a complete new cycle of 12, regardless of how many they have left. This has been established Doctor Who lore for a very long time:

  • In "The Five Doctors", The Master was given a new cycle of regenerations as incentive to rescue the doctor.
  • During the Time War, the Time Lords "resurrected" The Master, which presumably means giving him more regenerations, in order to help them fight.
  • At Trenzalore, they gave The Doctor 12 more regenerations to help him fight off The Daleks and save the universe or whatever.

That means, in theory, the returned Time Lords could give River more regenerations, if they wanted. What's not clear is if they could do that without risking a major paradox.

We know that time does not "really" work the way humans think, and that the Gallfreyans have figured out how to manipulate and move through it freely. However, there are limits to what can be done, and they mostly involve never changing anything that would lead to a paradox. In this case, River Song died in The Library, and The Doctor was there to see it. That likely influenced all of his future actions with regard to River. More to the point: The Doctor is the reason the Time Lords are free to return, but he did not make that possible until after River was dead.

So, it's all (obviously) timey-wimey, but my gut says that the Time Lords would not be able to give River any more regenerations, as it would prevent her from dying when she should have and likely cause major problems in The Doctor's timeline.

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    Good answer. Of course, if Moffat decides to bring the character back (with a different actress, of course) into the Doctor's life, her consciousness can be downloaded from the computer - where it still resides - and into a new body with a full regeneration set. I think. – Omegacron Feb 2 '15 at 15:42
  • if moffet wanted to bring her back as alex kingston I'm sure he'd pull something out of his ass :) – KutuluMike Feb 2 '15 at 17:59
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    @MichaelEdenfield For that, it could always just be earlier in her timeline. Or they could use her "ghost"/hologram, as they have before. – KSmarts Feb 2 '15 at 18:26
  • @MichaelEdenfield - it would be difficult, the actress is noticeably older now. The easiest solution would be to just put her in a body that's the first of a new regen cycle, thus easily explaining a different actress. – Omegacron Feb 2 '15 at 18:49
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    Don't give them ideas. .. – user16696 Feb 2 '15 at 19:26

When talking about River Song's regeneration power I always go back to a loophole in the episode "Let's Kill Hitler". Three questions of easy answer make me think she never lost all her regenerations.

Who said she used all her energy? Amelia Pond.

Now, we all know Amelia has no idea how to see the level of energy in a Time Lord or any other alien.

Who is the only one in that room with a tool able to read aliens and knowledge to understand the readings? The Doctor.

Last question: rule number one


I think there are a few issues confused in your question and your background to it:

River Song put her life energy, expended "all of her regenerations" into the 12th Doctor in "Let's Kill Hitler", and it was utilized - it saved his life.

She didn't literally put all of her regenerations into him. She had regenerated at least twice herself already, so she could only give him her remaining regenerations, possibly 10 or less.

Secondly - she didn't give him the energy to "store up" or even to regenerate him - she used it to heal him. He retained his present form.

What we have learned about regeneration energy since that time is that it can be 'gifted' to anyone - not just Timelords - to heal them. Twelve used it on the dying Davros in The Witches Familiar to heal his sight, joking that it might "cost him an arm or a leg" in the future (although Davros took far more than was offered). Evidently then, a "little" regeneration energy could heal something like sight - but far more was required from Riversong to restore life to Eleven.

But when Eleven faced death, he had no regeneration energy "stored up". The amount of energy Riversong gave him may have funded 10 regenerations of her own, but clearly it did not pass regenerations to The Doctor.


  1. A Timelord can "hold" enough regeneration energy for 12 full regenerations
  2. They can syphon of small amounts of that regeneration energy can be used to heal others
  3. Energy used for healing others is burned up - not stored for future regenerations
  4. New regeneration cycles (a new set of 12) can only be gifted by The Timelords

Technically, Riversong could have been gifted another regeneration cycle in the same way that The Doctor was at Trenzalore - but as the first occasion we were introduced to her was also her death, this may not be possible, especially if her death is a "fixed event" like The Doctor's presumed death was.

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