Roots: Brainstorm, Soylent Green (people help along miracle plant), TekWar. Gladiator movies (the Doctor's fate, dressed as a clown and subjected to a 'mock' battle to the death, is based on real events from the Coliseum). Jeremy quotes from the nursery rhyme 'Diddle Diddle Dumpling, My Son John'. Boys' Own adventure stories (Jeremy's patter). Sarah mentions Toy Town (Noddy). The Doctor alludes to the Watergate Scandal and the Nazi Nuremberg Tapes as well as King Lear ('nothing will come of nothing'), and Juvenal's 'panem et circenses'. Freeth butchers Casablanca ('this could be the end of a beautiful friendship'). The laser artillery in Episode 5 sounds very close to that of the TIE Fighters in the Star Wars movies.
Goofs: Script pages can be heard turning: when the Brigadier talks to Professor Willow, when the Doctor and the Brigadier are discussing Space World with Freeth, when the Brigadier asks the Doctor why the TARDIS took them to Blestinu, twice while the Brigadier is talking to the President, when the President mentions the Games, when the Doctor and the Brigadier discuss talking to the president and are ambushed by Tragen and twice when Freeth is telling the Doctor about his upcoming fight with Jenhegger. Phew.
The story is set between 'The Time Warrior' and 'Invasion of the Dinosaurs' (Sarah meets the Brigadier for the first time), which is impossible given that these two television adventures are consecutive. The Doctor sings the Venusian Lullaby in an attempt to calm the Gargon, but Sarah doesn't recognise it when he sings it to pacify Aggedor in 'The Monster of Peladon'
Pertwee's voice sometimes makes the Doctor sound like a dirty old man. If Earth is supposed to be unaware of what an alien species looks like, why bother changing the name of Space World's fake exhibits? Why not just paint a horse green? Aargh! [perhaps Freeth overestimate's UNIT's knowledge?]
Fluffs: The President's pronunciation of the phrase "sit on a cushion" in Episode 3 could have done with another take.
Technobabble: The Doctor explains the illusion of Space World as 'a radiated matrix of modulated psycho-magnetic beams'.
The TARDIS is equipped with a 'psycho-telemeter', which allows it to trace locations using forensic material samples from that origin.
Removing a flycar's speed governor 'risks feedback in the helical particle generator'.
To heal Onya's arm the Doctor 'reverses the pseudo-polarity of the metaphorical synapses in [her] putative energy channels'
Double Entendres: 'I am a peach ripe for the plucking'
'Now don't go over the top'
'We'll go down among the big huts'
Fashion Victims: At the Games, the Doctor faces Jenheggar clad only in his underwear.
Dialogue Disasters: 'You're as c-c-c-cold as an ice lizard you are, Rudley'.
From a football hooligan: 'Get up you great nerds'.
'Absolutely whizzo wicked!'
'I can't go riding 'round the Universe like Diddle-Diddle Dumpling, can I?'
'Wowie Zowie, look at the size of that - it's as big as a rugby pitch!'
Dialogue Triumphs: The Doctor on Freeth's incompetence: 'Appearances are not always deceptive'.
Sarah misinterprets the term Time Ram: 'Don't tell me, the TARDIS was attacked by a randy sheep with a clock for a face'.
Continuity: Space World is, purportedly, an entertainment venue on Hampstead Heath. It contains an Apollo rocket, at the top of which is an observation gallery and a revolving restaurant. Among the exhibits boasted are 'Ostroids', an alleged 'Crab-Clawed Kamelius' from the deserts of Aldebaran Two ('a small planet about the size of Venus'), and is guarded by six-foot sabre-toothed, reptilian dogs from the planet Blestinu - they have acidic saliva. Freeth has been on earth for thirty years, Blestinu is a planet at war [possibly with, but definitely involving, Parakon], with reptilian 'humans' and 'dogs' - the Doctor observes this as "parallel evolution" [i.e. evolutionary radiation].
Parakon is a self-styled 'paradise', home of the Parakon Corporation. Previously it had been a theocracy (Waldo's father, Carpal Rudley, had been a Temple Guard) until this was violently 'dissolved' by the Corporation. It now runs as a worldwide monopoly, with positions of authority given to company directors, and its inhabitants as shareholders. Its chief product is rapine, a miracle plant able to be synthesised into anything from metals to cutlery and food. It thrives in any climate, in any fertile soil, but is an environmental menace, requiring vast amounts of land and protein to be sustained. A small area of Parakon still without influence from rapine is known as 'the Lackan' and is home to exotic fruits (and a land-jelly fish that poses as fruit but devours its devourer from within), deer, trap lizards (which will only release their bite after decapitation), arrow serpents, and Gargans. Gargans, presumably, are gargantuan and have an excellent sense of smell, but poor eyesight and hearing. They live in caves and are fiercely territorial, marking their area with small rocks (despite their eyesight they will only attack anything that crosses this line). They have enormous teeth, and it is taboo to kill one.
Popular on Parakon are gladiatorial Games, flycars (which can be driven unattended if connected to 'city grids'), and Experienced Reality, [chiefly] a form of entertainment. Its technology is less akin to Virtual Reality than remote sensory reception with another individual, so that the participant can experience activities as they would (but cannot control them). It has thus become highly addictive, and is also used as a surveillance device. At the Games, the 'Great Butcher Toad', a beast the size of a small cow, is the main attraction.
'Blip juice' is so named because 'it sneaks up behind you and blips you'.
Unlike the Parakonians, Tragan is a Naglon - a sadistic creature with mauve skin and hairy warts. Pellonians are alien beings with tusks. A Venusian saying is "You'd swallow a Klakluk and choke on a Menian dustfly". The Klakluk is a large, skittish and confused Venusian creature with two heads 'so a pack of pattifangs couldn't creep up on it'.
As a boy the Doctor used to fly 'skimmers' on Gallifrey. He recalls losing a 'teacher', which was as painful for him as if his father had died (see: 'Doctor Who'. It is possible that this teacher may have been K'anpo, the Doctor being unaware of his current existence on Earth). He is able to prevent his death from falling by using 'bone relaxation', which involves a breakdown and regeneration of 'viable tissue' (this does not have to conflict with 'Logopolis' if we accept that the fourth Doctor was prepared to 'die' from his fall). His eyesight is so strong he can see hairs a millimetre in length unaided. Bessie has a mobile phone.
The Secretary General of the United Nations is female and European. The Brigadier considers himself 'pretty good' at lobbing grenades. Previous travels have seen him visit the Caribbean, and after his grandfather's death he drank the best malt Scotch he'd ever tasted.
Sarah's father used to shovel horse manure. Her current editor [at the Metropolitan?] is a woman named Clarinda.
Jeremy is a cub reporter for the same magazine.
Links: The Doctor says that 'reversing the polarity of the neutron flow' would sound ridiculous to a classical subatomic physicist. He uses Venusian Aikido against the guards in Episode 4 and the Venusian Lullaby (to no effect) on the Gargan in Episode 5 (he even name-checks Aggedor). References are made in Episode 1 to 'The Time Monster' and 'The Time Warrior'. The Blinovitch Limitation Effect is also mentioned.
Untelevised Adventures: Seeing the Gargan, the Doctor remarks that he hasn't seen teeth that size "since the last Tyrannosaurus Rex I met" (possibly unseen in 'Doctor Who and the Silurians' unless fan revision allows this story to be set after the events of 'Invasion of the Dinosaurs' - see 'Goofs'). The Doctor has been to Aldebaran Two before, and has previously encountered the Naglons, having 'had trouble with them a number of times'.
Location: Hampstead Heath, London mid-1972 [however, the last real Apollo moon mission was in December 1972, so for there to be an unused moon rocket at Space World the story would need to be set later than 1972. Also, the Doctor refers to Nixon and Watergate as a past event suggesting it is later than 1974, but then he might have had foreknowledge of the scandal] (there is a male Prime Minister (cf 'Terror of the Zygons') and the Winter Olympics are due next year), various zones of the planet Parakon, and Blestinu.
The Bottom Line: All credit to the BBC for bringing Doctor Who up to the modern age via radio and selecting the earliest surviving lead to play him; a shame it was only as far as 'Slipback'. With implied commentary on soap opera addiction, capital punishment, slavery and capitalism's destruction of the environment, 'Paradise' is a confused mess, overpopulated with unappealing and unengaging stereotypes and stock characters. Worse still, Sarah, a worthy companion solo, gets saddled with the comic relief device Jeremy. Still, it's the closest we got to a new audio adventure for the third Doctor