* In the part two of the serial Drathro's lackeys rifle through the Doctor's pockets to discover a bag of Jelly Babies, a signature treat commonly associated with the Fourth Doctor.

" He was disillusioned with the glory of death in combat after being mortally wounded while fighting the Headless Monks at the Battle of Demons Run, though, and he firmly corrected fellow nurse Rory Williams when the Doctor's companion called him a warrior, telling him, " I'm a nurse.

However, the Doctor's TARDIS has been seen to be able to fly through physical space, first in " Fury from the Deep " ( 1968 ) and at repeated times throughout the revived series, most notably in " The Runaway Bride " ( 2006 ), in which the TARDIS is shown launching into space ( most previous incidents show the TARDIS flying only after it has dematerialised from a location ).

" This does not apply when facing certain extremely advanced weaponry, often created after the Doctor's Type 40 TARDIS, such as Dalek missiles (" The Parting of the Ways "), for which the TARDIS requires additional shielding.

In " The Eleventh Hour " the TARDIS completely changes after crashing, and the Doctor's comment " What have you got for me this time?

Other than the Doctor and Susan, the Monk was the first member of the Doctor's race to appear in the programme, and the second Doctor Who villain ( after the Daleks ) to make a return appearance.

The Doctor hypothesised that the Monk left the Doctor's then-unnamed home planet, Gallifrey, some 50 years after the Doctor did.

( DWM # 147 ), in which the Sleeze Brothers hijack the Doctor's TARDIS in order to pursue the Monk across time and space after he damages their car.

In the episode " The Doctor's Daughter ", after landing on planet Messaline the Doctor was forced to place his hand inside a progenation machine, which used his DNA to create a new soldier, to fight in the war taking place.

* The Doctor's companion, Donna, became part Time Lord after touching the Doctor's severed hand, which had regenerative energy locked within it.

He also wears the Sixth Doctor's patchwork coat for much of the first episode, the first example of a Doctor wearing his previous self's clothes for a prolonged period rather than quickly changing after regeneration.

The Master springs yet another trap ; a trap door under the Doctor's feet leading to the vast sewers of Tersurus, which he intends to suggest to the architect after going back in time again and buying him an expensive dinner.

For example, after the broadcast of " Partners in Crime ", the strip portrayed the Doctor's arrival on the " Planet of the Hats ", referred to in the episode.

The race ( or nation ) the Thals were at war with was the Kaleds, who at the time of the fourth Doctor's arrival were a fascistic society involved in a generations-long war of attrition with the Thals ( whose use of slave labour did not make them much better, although all slaves were freed and given a blanket pardon after the war was over ).

Dr Holloway, who has resigned from her job at the hospital, after the hospital covering up the Doctor's presence there, takes the Doctor home.

While the Master begins the process of transferring the Doctor's remaining regenerations to him, Dr Holloway is able to connect the last power circuit in the console room, sending the TARDIS into a time-holding pattern just moments after the turn of midnight, staving off destruction of the Earth.

As Lee departs after returning the rest of the Doctor's possessions, the Doctor warns him not to be in San Francisco next year during New Year's Eve.

* Although the Doctor has never regenerated the same way twice ( although his 9th and 10th regenerations were similar to each other ), the depiction here is particularly unusual in that, unlike all previous ( and later ) regenerations, it sets in long after the Doctor's apparent " death ", a condition apparently caused by the anaesthetic in the Doctor's system.

A later episode, The Sound of Drums, may also support the link theory ; it is revealed that after falling into the Eye, the Master is revived by the Time Lords without the Doctor's knowledge.

The 2000 Big Finish audio play The Apocalypse Element attempts to explain this decision by introducing a plot point in which the eye of the Sixth Doctor's companion Evelyn Smythe is keyed to a Gallifreyan security system so as to confound enemy expectations by allowing entry only to the most unlikely of candidates, the Doctor speculating after the crisis is over that the TARDIS may retain some sensitivity to human eyes in the future.

During the " Forgotten " story arc, a publicly disbanded Squad has a run-in with Manhunter, after she unknowingly compromises a months-long undercover investigation into the Crime Doctor's villainous operations.

Events on Thoros Beta after the Doctor's removal continue, as it is shown that Ycranos was placed in a time bubble by the Time Lords to hold his arrival back at the lab until after Kiv's mind was successfully transplanted into Peri ; when Ycranos is freed of the bubble, he is distraught at the results of the operation, and fires wildly, killing Peri.

The Count's luck changes, however, after a chance reunion with an ex-servant of his, Figaro, who is currently working as a barber and therefore has access to the Doctor's home.

The centre of the village is the oldest part of Askham Bryan but it also includes the 18th century Nag's Head pub, the Victorian Doctor's House and the old school, which was closed in the 1960s when it merged with St. Mary's C. of E. Primary School in Askham Richard.

Alien Bodies subtly suggests that it is just the Eighth Doctor who is half-human, while other books ( such as Unnatural History and The Gallifrey Chronicles ) suggest that the Doctor's human mother is a Victorian Lady called Penelope Gate, and his Time Lord father is called Ulysses.

Terry Molloy has reprised his role as Davros in the spin-off audio plays produced by Big Finish Productions, mostly notably Davros ( taking place during the Sixth Doctor's era ), which, through flashbacks, explored the scientist's life prior to his crippling injury, which is attributed to a Thal nuclear attack ( an idea that first appeared in Terrance Dicks ' novelisation of Genesis of the Daleks ).

In 1991, he presented the Doctor Who video documentary release The Hartnell Years showcasing selected episodes of missing stories from the First Doctor's era.

The production was deliberately based on the Fourth Doctor's era and a conscious effort was made to use cues taken directly from episodes of that era.

However, the practical unavailability of these soundtracks forced the show's musical director, Mark Ayres, to utilize material mostly from the Fifth Doctor's era.

Some online sources such as the Doctor Who Reference Guide conclude that the story may be placed during the Seventh Doctor's era, since it is this Doctor and his companion who begin and ultimately resolve the core plotline.

" However, the Fourth Doctor era serial The Masque of Mandragora also introduced the idea that the TARDIS has at least one secondary console room, later confirmed in the Eleventh Doctor episode The Doctor's Wife.

* The Fifth Doctor's sequence in the novel The Eight Doctors – featuring the Eighth Doctor going through his own past to meet and assist his other selves – takes place after this episode, the Fifth Doctor travelling to the Eye of Orion to continue their earlier holiday only to be attacked by a renegade Time Lord from the Eighth Doctor's era using the Timescoop, forcing the two Doctors to defeat a Raston Warrior Robot and a Sontaran squadron.

The renovated TARDIS console room of the Fifth Doctor's era, first seen in the 20th Anniversary special The Five Doctors ( 1983 ).

The Third Doctor's era introduced many of the Doctor's more memorable adversaries.

The catchphrase most associated with the Third Doctor's era is probably " reverse the polarity of the neutron flow ".

As with the three other Doctors costumed during the John Nathan-Turner era, the above mentioned question marks on the Doctor's pullover and his umbrella handle continued the red question marked clothing motif that was introduced in the Fourth Doctor's final season and ended before the Seventh Doctor's regeneration.

Kismet Delgado, the widow of Roger Delgado, who had played the Master during the Third Doctor's era, was one of the voices for the Spiders.

This is only one of two times that the Cybermen appear during the Third Doctor's era ( a hallucination of one appears in The Mind of Evil ).

* The Doctor indicates he is 900 years old ; this is the first firm indicator of his age since the Fourth Doctor's era, suggesting that approximately 150 years has passed for the Doctor since that time.

During the Third Doctor's era, beginning in 1970, the theme tune was altered for the first time.

The Glynn arrangement was itself replaced by a new arrangement by Keff McCulloch for the Seventh Doctor's era beginning with Season 24 ( 1987 ).

With the arrival of a younger Doctor and changing tastes, the Second Doctor's tenure was characterised by a faster pace and a preference toward " monster of the week "- style horror stories, whilst the purely historical adventures that were a recurring feature of the Hartnell era ceased with The Highlanders, the only Troughton-era entry in that genre.

The Fifth Doctor's era was notable for a " back to the basics " attitude, in which " silly " humour ( and, to an extent, horror ) was kept to a minimum, and more scientific accuracy was encouraged by the producer, John Nathan-Turner.

UNIT became a prominent feature of Doctor Who throughout The Third Doctor's era, when the series was produced by Sherwin's successor Barry Letts.