History Recap / DoctorWhoS38E6Praxeus

Written by Pete [=McTighe=] and Creator/ChrisChibnall. This episode first aired February 2, 2020.

* InMediasRes: The episode starts with the Doctor and her companions already split up across the globe as part of their investigation in to the three distress calls they recieved in the previous episode.

Above the Indian Ocean, British astronaut Adam Lang's Soyuz descent capsule malfunctions suddenly, causing him to go missing. In Peru, travelling vloggers Gabriela and Jamila camp by a beautiful river that has become a polluted dump site, but when Jamila wakes up in the middle of the night, she's suddenly attacked by a bird. When Gabriela wakes up and finds her friend missing and dead birds lying about, she tries to touch one... only for Ryan to suddenly turn up and warn her not to do so, picking up the bird's corpse in the process. In the UK, troubled ex-policeman Jake Willis discovers that Adam — his husband — is missing, presumed dead, just before receiving several text messages from Adam asking for help and placing him in Hong Kong. When Jake arrives, he tries to kick down the door to the building where Adam apparently is, only to be met by Yaz and Graham, who have seen strange energy readings and have the skeleton keys to enter. In Madagascar, scientist Suki Cheng is annoyed when she is yet again beaten to work by her colleague Amaru when they are called to help rescue a man floating in the surf by the Doctor. The man, survivor of a missing US submarine, panics about something that got inside the vessel before his body is taken over by white scale-like growths and disintegrates.

The Doctor arrives alone in the TARDIS in time to witness Jamila's infection spread across her face and cause her to explode. The Doctor, Ryan, and Gabriela set off for Hong Kong and meet with Graham, Yaz, and Jake, who has just kicked down the door to the room where the energy readings are emanating from and discover Adam barely conscious in a strange alien lab. Yaz notices a translucent panel with alien language next to Adam and recognizes its value. The Doctor, Ryan, Gabriela, Graham, Yaz, and Jake evacuate Adam, but two humanoid figures in gas masks gang up on them. Jake subdues them in close combat and shoots them with one of their laser rifles.

In Madagascar, the Doctor and company discover that the growths have spread on Adam's face. The Doctor asks Suki if her lab has enough advanced medical equipment, up to a gene sequencer, and Suki confirms it. The Doctor asks Amaru to stay out in front and watch the birds while she studies the growths and Ryan dissects the bird corpse he brought along, which is full of plastic. Meanwhile, Graham assures Adam he knows how to take care of him with an IV drip, having been through cancer treatment; as they wait outside on the seashore for Adam to heal, Graham comforts Jake, who reveals he has an inferiority complex from being married to Adam; Jake also hates travelling abroad and is afraid to commit, which is why he wasn't present at Adam's launch. The Doctor finds the growths and the odd behaviour of the birds stem from an alien bacterium which attaches easily to plastics, including microplastics; the natural enzymes of the birds are trying to prevent the alien bacterium from spreading.

The Doctor locks onto Yaz's coordinates and lands the TARDIS in the plastic landscape. Yaz reunites with the Doctor, only for the Doctor to disappoint her by revealing they are underneath the Indian Ocean garbage patch, laden with plastic. The Doctor, Yaz, Graham, Ryan, and Gabriela find the wounded humanoid and unmask him, triggering his death from Praxeus. The five of them find Suki inspecting the engines of a small unpowered alien space ship. Suki reveals the ship is hers, and her race are almost dead from Praxeus, but have been able to hold off Praxeus because of their different metabolism. However, they cannot continue to thrive without finding an antidote, and had searched three galaxies before landing upon the perfect plastic-polluted planet on which to investigate Praxeus' effects: Earth.

The Doctor then notices Adam has grown healthy, proving the antidote worked, and that the ship has organic fuel cells. She realizes the fuel cells can be used to amplify the effects of the antidote and distribute it farther out. The Doctor, Yaz, Ryan, Graham, Jake, Adam, and Gabriela repair the ship and set it to fly into the stratosphere to explode and help destroy Praxeus. They escape the ship, only to find that the autopilot is not working and Jake has stayed behind to guide the ship to its final destination. Adam pleads to Jake not to sacrifice himself. Jake points out that he wants to, and must, do more to save the billions of lives on Earth. The Doctor rushes to materialize the TARDIS around Jake, though, saving him the millisecond before the ship explodes.

The Doctor drops Adam, Jake, and Gabriela off at the lab in Madagascar. Adam comments that he always wanted a honeymoon, and Jake relents, taking in the view in the meantime. The Doctor and Ryan encourage Gabriela to look for a new travel companion in Jake and Adam.

* ActorAllusion: The Doctor [[Series/{{Broadchurch}} runs down a beach toward a (soon to be) dead body]].
* AudienceSurrogate: The word "pathogen" is a reasonably common one. And while many people will not know its full scientific meaning (given that it's a scientific term that doesn't come up much in daily life, to be fair), the companions are once again clueless to what it means, again done so the Doctor can explain its meaning in more detail to the audience. Especially egregious in Graham's case, who was not only married to a nurse but also went through cancer treatments and the resulting immunosuppression, ''and'' bare minutes later "knows his way around an IV". Plus he's the oldest of the companions, and that alone should be enough to make him not knowing what it means unbelievable.

* BreatherEpisode: Another standalone episode with a mostly happy ending (the second in Series 12 after "[[Recap/DoctorWhoS38E4NikolaTeslasNightOfTerror Nikola Tesla's Night of Terror]]") kicks off the second half of a StoryArc-heavy season, right on the heels of the wringer that the Doctor was put through in "[[Recap/DoctorWhoS38E5FugitiveOfTheJudoon Fugitive of the Judoon]]". The {{Cliffhanger}} ending of that episode even suggests that the TARDIS is ''deliberately'' distracting her from her gloom by picking up the signals that lead into this crisis.

** The fam uses [[Recap/DoctorWhoS37E5TheTsurangaConundrum com-dots]] to stay in contact while spread out.

** Like Clara in seasons eight and nine, Yaz has a go at being the Doctor. Thirteen sounds both impressed and annoyed at Yaz putting herself in danger.
** When asked what's the worst that could happen while being teleported to an unknown destination, Yaz replies YouDoNotWantToKnow, because the first time this happened she and the rest of Team Tardis nearly died when they ended up in outer space.

* GeekyTurnOn: After TheReveal that Suki Chang is an ''alien'' scientist, the Doctor kicks herself for being too distracted by her surprisingly well-equipped lab and ability to match her technobabble.

* InMediasRes: The episode starts with the Doctor and her companions already split up across the globe as part of their investigation. The previous episode ended with them getting the three distress calls.
* InsistentTerminology: Jake is very firm that he's not a ''former'' policeman, he's on a sabbatical. Yaz, who also is on sabbatical from her police job is not impressed, as she doesn't claim to be a police officer while doing so.

** When Gabriela compliments Ryan on his build, he attributes it to doing "a lot of running".

* {{Understatement}}: Aramu's response to the TARDIS materializing in front of him is a surprisingly calm "Suki, this is not an ordinary day." Which makes sense when it's revealed they are both alien scientists.

JustForFun/TheOneWith plastic. No, not [[Recap/DoctorWhoS7E1SpearheadFromSpace t]][[Recap/DoctorWhoS8E1TerrorOfTheAutons h]][[Recap/DoctorWhoS27E1Rose e]][[Recap/DoctorWhoS31E12ThePandoricaOpens m]].

[[caption-width-right:350: An ocean full of plastic. The [[AnAesop aesop]] speaks for itself.]]

The one with plastic. No, not [[Recap/DoctorWhoS7E1SpearheadFromSpace t]][[Recap/DoctorWhoS8E1TerrorOfTheAutons h]][[Recap/DoctorWhoS27E1Rose e]][[Recap/DoctorWhoS31E12ThePandoricaOpens m]].

* InferredHolocaust: The Doctor creates a cure for Praxeus, hooray! But it only works on humans and will actually expediate Praxeus infections in Suki's species, and one of the last things Suki did before dying from it was beam the formula to her people. Who, assuming it works, will begin administering it as soon as it can be created. Bummer.

* {{Understatement}}: Aramu's response to the TARDIS materializing in front of him is a surprisingly calm "Suki, this is not an ordinary day."

* InsistentTerminology: Jake is very firm that he's not a ''former'' policeman, he's on a sabbatical.

** The aliens in HazmatSuits turn out to be infected victims trying to find a cure, making it look like they're another NonMaliciousMonster. Then Suki reveals they infected the Earth so Praxeus would be TestedOnHumans to see how it develops.

* BaitAndSwitch: Adam is left on the TARDIS with Jake while the Doctor's cure runs its course. The instruments on the TARDIS start beeping and glowing red while Adam appears to be getting worse. A bit later, Jake shows up with Adam, who is fine thanks to the cure.

** An alien invasion is defeated by [[Literature/TheWarOfTheWorlds Earth's natural defences]].

* ShoutOut: The Praxeus victims developing crusts on their skin and exploding into dust is similar to the time-delayed death of an apparent survivor of an alien attack in the final ''Franchise/{{Quatermass}}'' serial. An astronaut returning to Earth infected by an alien virus is also similar to the first Quatermass serial.

* ChekhovsGun: Jake is trying to kick down a heavy metal door when Yaz and Graham arrive and [[WeHaveTheKeys unlock it with a skeleton key]]. Inside the building, Yaz and Graham find a flimsier wooden door which is also locked and try to figure out how to bypass it... until Jake lightly pushes Yaz aside and kicks it in.

* PlotDrivenBreakdown: The autopilot on the alien shuttle happens to break down moments after the Doctor notes that she's set it precisely so they won't be drowned by the ocean when the shuttle launches out of the garbage construct. Jake takes over so they can escape in the TARDIS and still stop Praxeus.

* BreatherEpisode: Another standalone episode with a mostly happy ending (the second in Series 12 after [[Recap/DoctorWhoS38E4NikolaTeslasNightOfTerror "Nikola Tesla's Night of Terror"]]) kicks off the second half of a StoryArc-heavy season, right on the heels of the wringer that the Doctor was put through in [[Recap/DoctorWhoS38E5FugitiveOfTheJudoon "Fugitive of the Judoon"]]. The {{Cliffhanger}} ending of that episode even suggests that the TARDIS is ''deliberately'' distracting her from her gloom by picking up the signals that lead into this crisis.

** Like Clara in seasons eight and nine, Yaz has a go at being the Doctor. Thirteen sounds both impressed and annoyed at Yaz putting herself in danger.

** For the third time, the Doctor [[Recap/DoctorWhoS27E10TheDoctorDances materializes the TARDIS]] [[Recap/DoctorWhoS34E2IntoTheDalek around a ship about to explode, saving its occupant]].

** When the Doctor discovers that plastics are closely linked to the threat of Praxeus, her first thought is to suspect Auton involvement, but she quickly dismisses that because the Autons aren't bacterial in nature.

* NoBiochemicalBarriers: Played straight by Praxeus itself, which is equally as deadly to Earth lifeforms as it is to Suki's species, but averted by the cure the Doctor develops; the Doctor specifically created it to work on Earth lifeforms and when Suki tries to use the cure on herself, it only hastens the rate at which the Praxeus infection kills her.
** There's even a bit of TruthInTelevision in that the virus kills Suki and the other aliens more slowly as it evolved on their planet and so would be better adapted to their physiology, even if it's not adapted enough not to kill them.
* NoBodyLeftBehind: The human victims of Praxeus explode into dust as the infection kills them.

* BadassGay: Jake is a HotBlooded ex-CowboyCop with a penchant for kicking down doors. And even though he spends most of his screen time sick with Praxeus, Adam is an astronaut and TheAce.

** The Doctor materializes the TARDIS [[Recap/DoctorWhoS34E2IntoTheDalek around a ship about to explode, saving its occupant]].

The Doctor locks onto Yaz's coordinates and lands the TARDIS in the plastic landscape. Yaz reunites with the Doctor, only for the Doctor to disappoint her by revealing they are underneath the Indian Ocean garbage patch, laden with plastic. The Doctor, Yaz, Graham, Ryan, and Gabriela find the wounded humanoid and unmask him, triggering his death from Praxeus. The five of them find Suki inspecting the engines of a small unpowered alien space ship. Suki reveals the ship is hers, and her race are almost dead from Praxeus, but have been able to hold off Praxeus because of their different metabolism. However, they cannot continue to thrive without finding an antidote, and have been searching three galaxies before landing upon the perfect plastic-polluted planet on which to investigate Praxeus's effects: Earth.

The Doctor locks onto Yaz's coordinates and lands the TARDIS in the plastic landscape. Yaz reunites with the Doctor, only for the Doctor to disappoint her by revealing they are underneath the Indian Ocean garbage patch, laden with plastic. The Doctor, Yaz, Graham, Ryan, and Gabriela find the wounded humanoid and unmask him, triggering his death from Praxeus. The five of them find Suki inspecting the engines of a small unpowered alien space ship. Suki reveals the ship is hers, and her race are almost dead from Praxeus, but have been able to hold off Praxeus because of their different metabolism. However, they cannot continue to thrive without finding an antidote, and have been searching three galaxies before landing upon the perfect plastic-polluted planet on which to investigate Praxeus' effects: Earth.

* AudienceSurrogate: The word "pathogen" is a reasonably common one. And while many people will not know its full scientific meaning (given that it's a scientific term that doesn't come up much in daily life, to be fair), the companions are once again clueless to what it means, again done so the Doctor can explain its meaning in more detail to the audience. Especially egregious in Graham's case, who was not only married to a nurse but also went through cancer treatments and the resulting immunosuppression, ''and'' bare minutes later "knows his way around an IV". Plus he's the oldest of the companions, and that alone should be enough for him to not know what it means unbelievable.

The Doctor arrives alone in the TARDIS in time to witness Jamila's infection spread across her face and cause her to explode. The Doctor, Ryan, and Gabriela set off for Hong Kong and meet with Graham, Yaz, and Jake, who has just kicked down the door to the room where the energy readings are emanating from and discover Adam barely conscious in a strange alien lab. Yaz notices a translucent panel with alien language next to Adam and recognized its value. The Doctor, Ryan, Gabriela, Graham, Yaz, and Jake evacuate Adam, but two humanoid figures in gas masks gang up on them. Jake subdues them in close combat and shoots them with one of their laser rifles.

* BreatherEpisode: Another standalone episode with a mostly happy ending (the second in Series 12 after [[Recap/DoctorWhoS38E4NikolaTeslasNightOfTerror "Nikola Tesla's Night of Terror"]]) kicks off the second half of a StoryArc-heavy season, right on the heels of the wringer that the Doctor was put through in [[Recap/DoctorWhoS38E5FugitiveOfTheJudoon "Fugitive of the Judoon"]]. The {{Cliffhanger}} ending of that episode even suggests that the TARDIS is ''deliberately'' distracting her from her gloom by picking up the signals that leads into this crisis.

The Doctor arrives alone in the TARDIS in time to witness Jamila's infection spread across her face and cause her to explode. The Doctor, Ryan, and Gabriela set off for Hong Kong and meet with Graham, Yaz, and Jake, who has just kicked down the door to the room where the energy readings are emanating from and discovered Adam barely conscious in a strange alien lab. Yaz has noticed a translucent panel with alien language next to Adam and recognized its value. The Doctor, Ryan, Gabriela, Graham, Yaz, and Jake evacuate Adam, but two humanoid figures in gas masks gang up on them. Jake subdues them in close combat and shoots them with one of their laser rifles.

Above the Indian Ocean, British astronaut Adam Lang's Soyuz descent capsule malfunctions suddenly, causing him to go missing. In Peru, travelling vloggers Gabriela and Jamila camp by a beautiful river that has become a polluted dump site, but when Jamila wakes up in the middle of the night, she's suddenly attacked by a bird. When Gabriela wakes up and finds her friend missing and dead birds lying about, she tries to touch one... only for Ryan to suddenly turn up and warn her not to do so, picking up the bird's corpse in the process. In the UK, troubled ex-policeman Jake Willis discovers that Adam — his husband — is missing, presumed dead, just before receiving several text messages from Adam asking for help and placing him in Hong Kong. When Jake arrives, he tries to kick down the door to the building where Adam apparently is, only to be met by Yaz and Graham, who have seen strange energy readings and have the skeleton keys to enter. In Madagascar, scientist Suki Cheng is annoyed when she is yet again beaten to work by her colleague Amaru, when they are called to help rescue a man floating in the surf by the Doctor. The man, survivor of a missing US submarine, panics about something that got inside the vessel before his body is taken over by white scale-like growths and disintegrates.

The Doctor arrives alone in the TARDIS in time to witness Jamila's infection spread across her face and cause her to explode. The Doctor, Ryan, and Gabriela set off for Hong Kong and meet with Graham, Yaz, and Jake, who has just kicked down the door to the room where the energy readings are emanating from, and discovered Adam barely conscious in a strange alien lab. Yaz has noticed a translucent panel with alien language next to Adam, and recognized its value. The Doctor, Ryan, Gabriela, Graham, Yaz, and Jake evacuate Adam, but two humanoid figures in gas masks gang up on them. Jake subdues them in close combat and shoots them with one of their laser rifles.

In Madagascar, the Doctor and company discovers the growths have spread on Adam's face. The Doctor asks Suki if her lab has enough advanced medical equipment, up to a gene sequencer, and Suki confirms it. The Doctor asks Amaru to stay out in front and watch the birds while she studies the growths and Ryan dissects the bird corpse he brought along, which is full of plastic. Meanwhile, Graham assures Adam he knows how to take care of him with an IV drip, having been through cancer treatment; as they wait outside on the seashore for Adam to heal, Graham comforts Jake, who reveals he has an inferiority complex from being married to Adam; Jake also hates travelling abroad and is afraid to commit, which is why he wasn't present at Adam's launch. The Doctor finds the growths and the odd behaviour of the birds stem from an alien bacterium which attaches easily to plastics, including microplastics; the natural enzymes of the birds are trying to prevent the alien bacterium from spreading.

* FiveFiveFive: Or at least the British equivalent, 07700 900xxx. Unfortunately the producers made a small mistake as the phone number displayed is +852 7700 900xxx, which is a British phone number preceded by the IDD code for Hong Kong. In RealLife, IDD codes are tied to the phone number and don't change depending on where you are.

* AudienceSurrogate: The word "pathogen" is a reasonably common one. And while many people will not know its full scientific meaning (given that it's a scientific term that doesn't come up much in daily life, to be fair), the companions are once again clueless to what it means, again done so the Doctor can explain its meaning in more detail to the audience. Especially egregious in Graham's case, who was not only married to a nurse, but also went through cancer treatments and the resulting immunosuppression, ''and'' bare minutes later "knows his way around an IV". Plus he's the oldest of the companions, and that alone should be enough for him to not know what it means unbelievable.

* BreatherEpisode: Another standalone episode with a mostly happy ending (the second in Series 12 after [[Recap/DoctorWhoS38E4NikolaTeslasNightOfTerror "Nikola Tesla's Night of Terror"]]) kicks off the second half of a StoryArc-heavy season, right on the heels of the wringer that the Doctor was put through in [[Recap/DoctorWhoS38E5FugitiveOfTheJudoon "Fugitive of the Judoon"]]. The {{Cliffhanger}} ending of that episode even suggests that the TARDIS is ''deliberately'' distracting her from her gloom by picking up the signals that lead into this crisis.

* GreenAesop: Gabriela takes Jamila to a river in Peru which she describes as the most beautiful river in the world, and finds its banks have become strewn with trash in the 3 years she was last there. Plastic pollution turns out to be central to the threat posed by Praxeus, and there are a few rants against humans introducing plastic into the foodchain.

* HumanAliens: Suki belongs to an unnamed human-looking alien race that came to Earth to develop a cure for Praxeus. The Doctor, a Human Alien herself, doesn't realise she's alien until she is tipped off.

* ShoutOut: The Praxeus victims developing crusts on their skin and exploding into dust is similar to the time-delayed death of an apparent survivor of an alien attack in the final ''Franchise/{{Quatermass}}'' series. An astronaut returning to Earth infected by an alien virus is also similar to the first Quatermass series.

* {{Understatement}}: Aramu's response to the TARDIS materialising in front of him is a surprisingly calm "Suki, this is not an ordinary day."