Jack was shot by a Dalek and then brought back to life by Rose, Rose couldn't control what she was doing so she brought him back to life forever, Jack is now immortal. The Doctor wasn't comfortable with what had happened so he ran from the scene leaving Jack behind on Satellite 5.
After he was shot and killed by a Dalek, Jack was revived by Rose Tyler, who at the time was transformed into a nearly omnipotent being. Unable to control her powers, she accidentally turned him into an immortal being.
As a consequence of his death and resurrection in the Series 1 finale, "The Parting of the Ways", Jack becomes immortal and is stranded on 19th-century Earth. There he becomes a member of Torchwood, a British organization dedicated to combating alien threats.
Is Captain Jack Harkness immortal because of Rose Tyler? According to the Doctor, when Rose was possessed by the heart of the TARDIS she brought him back to life and made him a 'fixed point in time' which prevents him from being changed by outside forces. So yes, he's unkillable.
One of the Futurekind shorts the system out, filling the room with the rocket couplings with deadly radiation. Jack is enlisted to fix the couplings. While Jack is inside working, the Doctor admits he abandoned Jack purposely because of the immortality Rose granted to Jack. Jack readies the rocket for launch.
Theta Sigma (ΘΣ) is given as the Doctor's name in TV: The Armageddon Factor. This is retconned to be the Doctor's "nickname at college" in TV: The Happiness Patrol. The names ∂³Σx² and ΘΣ both contain the Greek letter sigma (Σ). The Doctor's real name was spelled as "d³ᓬx²" in Marvel Premiere #57.
Captain Jack Harkness was one of the Doctor's foremost allies, but the Eleventh and Twelfth Doctors never met him. Why did Jack disappear until now? Doctor Who's Captain Jack Harkness was a longtime ally of Doctors Nine and Ten, but then he disappeared from the scene until his recent arrival to help Thirteen.
Captain Jack Harkness becomes the Face of Boe in Doctor Who, revealed in season 3 as a nickname he used. The show never officially confirms how Jack transforms, but it can be traced back to the season 1 finale when Rose Tyler saves him from death.
Jack was shot by a Dalek and then brought back to life by Rose, Rose couldn't control what she was doing so she brought him back to life forever, Jack is now immortal. The Doctor wasn't comfortable with what had happened so he ran from the scene leaving Jack behind on Satellite 5.
Jack Sparrow probably didn't want to turn into a zombie. Jack is also familiar with another price of immortality… the Flying Dutchman is a legendary ghost ship that can never make port and is doomed to sail the oceans forever.
Apparently, Time Lords can only regenerate a maximum of twelve times in a single regenerative cycle. After that, they die. However, the Time Lords have been able to give certain members of their society additional regenerative cycles.
The Face remained a mystery until the conclusion to Doctor Who season 3, when Harkness casually mentioned that "The Face of Boe" was an old nickname he used to go by. Upon hearing this, the Doctor and Martha mentally join the dots and realize that their giant head friend is actually Captain Jack in the far future.
"Captain Jack Harkness" was the alias adopted by Time Agent and con man Javic Piotr Thane (AUDIO: Month 25) from the 51st century who became an associate and occasional companion of the Doctor.
Jack Harkness was a human who worked for Torchwood. After meeting Alonso Frame, thanks to the Doctor, he eventually returned to Torchwood, where he, Martha Jones, and Mickey Smith continued their work. Later on, they met Clara Oswald and Ashildr, who they had further adventures with.
Jack doesn't exactly regenerate; he became something 'fixed' in time; he's not regenerating, so much as returning to a previous state. Essentially, Bad Wolf created the Head of Bo. Ergo, there's a consciousness guarding his perpetual existence, in a manner of speaking.
Throughout the first three Pirates of the Caribbean films, Captain Jack Sparrow's character arc focused significantly on his search for immortality — perhaps for too long. Jack Sparrow was the kind of character that wanted to be virtually untouchable — the best pirate there had ever been.
Discussing whether his character could ever find a soulmate, John Barrowman refutes that Jack "likes everybody, and his love for each person is different". He believes that Jack does harbour romantic feelings toward the Doctor, but "would never take that beyond infatuation" and "would never let the Doctor know".
Each, in their own way, was affected by their travels and became bigger than themselves. They all helped the Doctor survive, across space and time. But Rose Tyler did it first. She fell in love with the Doctor, and he loved her.
Clara was forced to face the Raven, killed by the touch of a Quantum Shade. However, death would not be the end for the impossible girl, and using Time Lord technology, the Doctor was able to extract Clara a second before her death, between one heartbeat and the next.
Jack is approached by a reincarnated Bootstrap Bill Turner, Will's long-deceased father, who reveals he is now part of the crew of The Flying Dutchman captained by Davy Jones, and Jack must pay his debt to him - Jack asking Jones to raise his ship from the depths and make him captain for thirteen years.
Three days into the voyage, the first mate of the Pearl, Hector Barbossa, tricked Captain Jack Sparrow into giving up the bearings to Isla de Muerta. That night, mutineers led by Barbossa overtook the Black Pearl and marooned their former captain to die on a deserted island.
There are perhaps a few reasons for this. The first is that Torchwood were aware of the Doctor's time-travelling nature. They may even have eventually learned of the exact order that his or her incarnations occur in. At the very least, they probably learned that it was best to avoid any Doctor unless it was the Tenth.
So when the Doctor has a death wish, when he's more interested in sacrificing himself to save his soul than in living to save another day, his instincts take over. He regenerates into a Doctor that's more alien, more disconnected, more juvenile, more ruthless, and less able to accept his own mortality.
The Doctor loved River Song enough that he suppressed the urge to roam for over two decades. This is something he was never able to do before River, and has never done again since.
