The Doctor suggests a "kind of St. Elmo's fire" is responsible for the halo of light that momentarily surrounds him. There are a few possible alternatives. Firstly: something brand new that’s impossible to predict (e.g. Skithra revenge fleets, the Master and the Cyber Lords get melded together, an evil version of W.A.S.P from Stingray). It’s probably going to be that really isn’t it?

K-9 is awesome of course, but he’s plagued with power problems, which unfortunately precedents THE major trope that lessens his usefulness in the future. They fight off the infected humans, but are again without sufficient weaponry to destroy the Nucleus, or its many children, which are about to hatch as "macro-sized" beings, like the newly macro-sized Nucleus. The Doctor jams the door they are behind and rigs a gun to fire into a cloud of oxygen gas he is releasing and escapes. As intended, when the Swarm finally forces open the door, the blaster fires, igniting the oxygen in Titan's methane atmosphere and destroying the Swarm and the base. The Swarm remained dormant in the TARDIS' computer until the Doctor's seventh incarnation. Shortly afterwards, the Doctor returned to Titan Base in the company of Ace and Hector Thomas in 4920. The TARDIS had been commandeered by Hector, who had fallen under the control of the Swarm. It ensured its own creation by returning to the Bi-Al Foundation, where it mutated from the Saturnian plague. ( AUDIO: Revenge of the Swarm)

Tropes:

The first establishing shot of the Bi-Al Foundation shows it with the damage later caused by the shuttle crash.

In 2010, Mark Braxton of Radio Times awarded it two stars out of five, contrasting it with the Philip Hinchcliffe era and describing it as "a kidified, Poundland Star Wars". He felt "many of the effects are excellent" but observed a "precarious juxtaposition" between good and bad effects and "the ambition of the serial as a whole". He praised the story as a "romping yarn" which "brings out the best in veteran designer Barry Newbery", but criticised "unbelievably incompetent" action scenes, as well as "harsh lighting" and "pristine white sets". He also commented on Louise Jameson as looking "unsurprisingly ill at ease" despite giving "her usual 100 per cent". [2] DVD Talk's John Sinnott disliked the way K9 was used too conveniently and found the plot too similar to Fantastic Voyage (1966), but less well done. He praised the visual effects of the inside of the Doctor's head, but criticised the other sets. [8] Commercial Releases [ edit ] In print [ edit ] Doctor Who and the Invisible EnemyGenetic Memory: The clones of the Doctor and Leela have the memories of their originals. K9 explains that this is because they are more like "biological photocopies" than proper clones, hence their shortened lifespans. Which does not in any satisfactory way explain how they cloned their clothes. Homaged much later on in "The Doctor's Daughter". The Invisible Enemy is the second serial of the 15th season of the British science fiction television series Doctor Who, which was first broadcast in four weekly parts on BBC1 from 1 to 22 October 1977. The serial introduced the robot dog K9, voiced by John Leeson. In the serial, an intelligent virus intends to spread across the universe after finding a suitable spawning location on the moon Titan. When the Doctor, Leela and K9 first leave the Bi-Al Foundation in the TARDIS in part four, Professor Maruis is visibly stood next to the TARDIS as the Doctor enters, waving him goodbye. However, in the subsequent wide shot of the TARDIS dematerialising, he has disappeared. Oh, God, the Doctor's furry hand. Spare us. Not to mention that silly face fuzz they all start sprouting. Studio Sweepings - A rare opportunity to go behind the scenes on the recording of this story, courtesy of a time-coded videotape recording

Working titles for this story included [The] Invisible Invader, The Invader Within, and The Enemy Within. [2] Fantastic Voyage" Plot: At one point, the Fourth Doctor has himself and Leela cloned and shrunk down so he can be injected into his own brain, and fight the monster that's nesting inside it. When K9 shoots one of the infected men, the blast beam appears to come out of his eyes, then moves down to his snout as the camera moves. Bi-Al Members - Leslie Bates, Ken Sedd, Alan Clements, Cy Town, Derek Hunt, Margot Gordon ( DWM 271)

More clips from Doctor Who (1963–1996)

The Doctor says he has lost the ability to tune his brain's Reflex Link with "The Time Lord Intelligentsia - a thousand super-brains in one." The Invisible Enemy was the second serial of season 15 of Doctor Who. It saw the first appearance of K9. Visible Boom Mic: When the Doctor is congratulating himself on blowing up the Swarm, the shadow of a boom mike can be seen. Secondly: a return to the Leisure Hive (from ‘The Leisure Hive’) based purely on the connective tissue between the words ‘Hive’ and ‘Swarm’. This story was released on DVD on 16 June 2008 in the K9 Tales Box Set. It was released in the box set alongside K9 and Company.

Clothing-Concealed Injury: The station manager, Lowe, is taken over by The Virus. As the infection manifests with a strange growth around the eyes, Lowe conceals his infection by donning a pair of blast goggles and telling people his eyes had been injured during the explosion, making him very sensitive to light. Leela and the Doctor decide to create clones of themselves, which will then be shrunk and inserted into the Doctor. There they will destroy the Nucleus and escape through a tear duct. In the meantime, Leela and K9 fight off the infected staff of the hospital. The plan goes awry, allowing the Nucleus to escape and become human sized. The Nucleus and the infected staff leave for Titan Base so the Nucleus can spawn.

Enter The Whoniverse

John Leeson later reprised his role as the Nucleus of the Swarm in the audio story Revenge of the Swarm in 2014. Michael Sheard (Laurence Scarman) as usual does a good job as Lowe, although it's a thankless part. Doctor Who Series 13 Cast: Game Of Thrones’ Grey Worm Actor To Play Action Hero ‘Vinder’ By Louisa Mellor Inhuman Eye Concealers: The station manager, Lowe, is taken over by The Virus. As the infection manifests with a strange growth around the eyes, Lowe conceals his infection by donning a pair of blast goggles and telling people his eyes had been injured during the explosion, making him very sensitive to light.