Roots: The Firefly episode “Out of Gas” and The West Wing episode “In the Shadow of Two Gunmen”. There's a reference to the Millennium Bug.
Goofs: The bombs go off right next to everyone and are powerful enough to bury everyone in rubble, yet Ianto only suffers a dislocated arm and Owen and Tosh are unhurt.
The Doctor's hand appears to already be in Torchwood Three in 1999, when it shouldn't be there until at least Christmas 2006. Also in this scene, Alex says it's the 21st century, when he's a whole year early.
Tosh's job in 2004 has a surprisingly large number of LCD monitors [well it is a highly advanced research facility].
Is it really UNIT's job to track down people who steal stuff from government research establishments? Or to imprison them indefinitely without any legal process?
How is a pterodactyl able to lift Jack off the ground? [It's an alien that just looks a bit like a pterodactyl and has some weird antigravity ability.]
Jim diagnoses Kate's memory problem, but is also the brain surgeon who attempts to remove the alien. Surely these are entirely separate specialisms.
Continuity: Weevils have a distinct energy pattern [this is the rift energy pattern from their point of origin.]
Jack has died over 1392 times since he was recruited to Torchwood, having been killed fourteen times in the six months before that. He severed links between Torchwood One and Torchwood Three some time between January 2000 and Army of Ghosts/Doomsday.
UNIT have detention facilities where prisoners are held indefinitely and not given legal representation or any right of appeal.
Torchwood is able to edit CCTV footage.
Whilst much of our history of Torchwood Three comes from this episode, there are numerous flashbacks allowing us to put together a timeline of the organisation, albeit one with many gaps.
Torchwood Three was founded before the turn of the twentieth century. At some point in the 1890s there were two female staffers, including the leader. They were aware of the Cardiff rift and recruited Jack Harkness to the institution.
In 1901 Torchwood found another version of Jack Harkness who had been buried alive and put him into cold storage (Exit Wounds). Their staff included a white woman and a black man.
In 1909 Jack Harkness may have been seconded to the British Army in Lahore (Small Worlds, though this might have been during his time as a time traveller).
In 1918 Torchwood Three staff included Gerald and Harriet Derbyshire (who later died aged 26), who put the soldier Tommy Brockless into cryogenic suspension following interaction with future Torchwood staff. Jack Harkness may have spent some time posted to the Western Front during the war (To The Last Man).
In the late 1920s Jack Harkness was investigating the Night Travellers, but did not find anything (From Out Of The Rain).
By 1999 Torchwood staff included a man called Alex, who killed everyone except Jack and put him in charge. At some point after this Jack severs ties with Torchwood One, though the two seem to share personnel records.
Early on in this period Jack sets up a facility on Flat Holm Island to look after people who were lost through the rift but then returned. He keeps this secret from all the other Torchwood staff (Adrift).
It is unclear when Jack recruited Suzie Costello, but it must have been before late 2005 since she was working at Torchwood then (They Keep Killing Suzie).
In 2003 Jack recruits Toshiko Sato, calling in favours from UNIT - who have imprisoned her after she stole classified blueprints and built the device they described even though the blueprints were wrong.
In 2006 Doctor Owen Harper begins working at Torchwood, following his fiance's brain playing host to an alien parasite. Owen's flashback here must take place over a very long time period to fit with Tosh's statement in Exit Wounds that Aliens of London was in Owen's second week on the job.
In 2007, shortly after the fall of Torchwood One, Ianto Jones - a Torchwood One employee - successfully persuaded Jack to give him a job there. Ianto would install his partially-Cyberised girlfriend Lisa Hallett in the basement. Cyberwoman).
Police officer Gwen Cooper joined Torchwood shortly afterwards, after stumbling across a Torchwood operation (Everything Changes). She effectively replaced Suzie Costello, who died during these events.
Owen Harper died, but kept on walking in September 2008 (Reset/Dead Man Walking/A Day in the Death.
Toshiko Sato died and Owen Harper's body was destroyed in 2009 (Exit Wounds).
Torchwood Three itself was destroyed in September 2009, with Ianto Jones dying a few days later (Children of Earth).
Links: Jack mentions the Doctor uses the Cardiff rift to refuel ([tv]Boom Time/[tv]). The girl giving the tarot card reading also appeared in Dead Man Walking. The sonic modulator is presumably related to the Doctor's sonic screwdriver. There are references to Lisa Hallet (Cyberwoman) and Suzie (Everything Changes/They Keep Killing Suzie. Captain John was previously seen in Kiss Kiss, Bang Bang and Gray in Adam.
Extras: This episode of Torchwood had an episode of Torchwood: Declassified.
Location: Cardiff, in the late Victorian era, 1999, c.2008, c. 2009. The UK c. 2004, c. 2005
Unrecorded Adventures: Jack is said to have repeatedly undertaken unauthorised activities in attempts to find the Doctor. On New Years Eve 1999 he encountered a creature with 18 legs stacked with poison. He says he once dated a guy with no mouth and that he was on Earth when the asteroid that killed the dinosaurs hit.
The Bottom Line: 'Give this place a purpose before it's too late. It's interesting to see a backstory to how everyone joined Torchwood, but this episode is just a series of short flashbacks rather than a story in itself.