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.
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.
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".
The doctor leaves because he doesn't want to watch his friends die while he stays the same. He says so himself so why would he leave jack? Yes, jack would age but he wouldn't die and knowing him, he would keep going until he was a head in a jar.
The Doctor Reveals why he abandoned Jack | Daily Dose of Doctor Who | David Tennant | John Barrowman
Is Jack actually the Face of Boe?
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.
Clara is the future child of the Doctor and River who's had her memory erased. The two Time Lords must be up to something on their nights away from River's prison cell.
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.
This isn't really a thread the show picks up on again; at the end of the three-parter, the Doctor asks Jack to travel with him again, and in Journey's End the TARDIS lets him fly her no problem at all.
After the Tenth Doctor's hand was severed by a sword during the Sycorax invasion of Earth ("The Christmas Invasion"), the hand was recovered by Jack Harkness.
To some, companion Rose Tyler was the greatest love of the Doctor's life. He seemed to have a closer bond with her than almost anyone he'd travelled with before, and as time went on it was increasingly clear that she was deeply in love with him.
Perhaps not a character on Doctor Who, but surely the Doctor's greatest love throughout all time and space is the TARDIS. Far more than just a machine, the TARDIS is a living being and is the only traveling companion that has remained with the Doctor throughout all their adventures.
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.
Settling into her new life with the Meta-Crisis Doctor, Rose later became pregnant and gave birth to a daughter. Years later, she was briefly transported to her original universe and met the Eighth and Eleventh Doctors, after which she returned to her family.
In the time period, only women and children were allowed on the lifeboats first. Rose loved Jack too much to let him possibly die, so stating she wouldn't get on before Jack meant they crew would HAVE to let Jack on if they wanted Rose to live.
He can regenerate fully destroyed limbs or body parts, recover his life-force. Each time Jack came back to life, he would awaken with a very deep gasp of breath as his respiratory system resumed its functions.
Over his (very) long life, Captain Jack Harkness has been many things. Revived and made immortal by Rose Tyler after she'd absorbed the power of the Time Vortex, Jack travelled back to 1869, where his vortex manipulator burned out.
When we first met the Doctor, the inside of his TARDIS was a brilliant white marvel. It had a magnificent, hexagonal control console, originally designed to be flown by six pilots.
He spends over a century waiting to reunite with the Doctor, over which time he becomes the leader of the Torchwood branch in Cardiff. He later reunites with the Tenth Doctor (David Tennant) and Thirteenth Doctor (Jodie Whittaker) for further stints on Doctor Who.
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.
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.
Jamie McCrimmon accompanied the Second Doctor in 113 episodes, far more than any other companion. Frazer Hines happened to be working on the show during one of its busiest times ever and stayed with the program at the request of Patrick Troughton who wished to have Jamie and The Doctor together until the end.
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.
Now, obviously there are a few holes in this theory – Clara and River have actually met before in 2013's The Name of the Doctor, albeit when River was already a data ghost, so there probably would have been more recognition – but despite the relatively circumstantial evidence, we kind of like the idea of two Doctor Who ...
