• Jodie Whitaker (The Doctor)
• Bradley Walsh (Graham O'Brien)
• Mandip Gill (Yasmin Khan)
• Tosin Cole (Ryan Sinclair)
• Stephen Fry (C)
• Sacha Dhawan (O)
• Lenny Henry (Daniel Barton)
• Shobna Gulati (Najia Khan)
• Ravin J Ganatra (Hakim Khan)
• Bhavnisha Parmar (Sonya Khan)
• Melissa De Vries (sniper)
• Sacharissa Claxton (passenger)
• William Ely (older passenger)
• Brian Law (Operative (US))
• Buom Tihngang (Tibo)
• Asif Khan (Sgt Ramesh Sunder)
• Andrew Bone (Mr Collins)
• Ronan Summers (rendition man)
• Christopher McArthur (Ethan)
• Darron Meyer (Seesay)
• Dominique Maher (Browning)
• Struan Rodger (voice of Kasaavin)

A sniper waits on a hill on the Ivory Coast. Just as her target is approaching, something emerges from the rock behind her and attacks.

A plane begins its descent into Tokyo. A man walks up the aisle and hands a washbag over to a seated woman, asking if the bag is hers - he found it in the aisle. Thanking him, the woman goes into the toilet, opens the bag, retrieves a coded message and photographs it. Then something emerges from the wall and attacks her.

In Moscow a man arrives at the safehouse, hoping it will not be long before the extraction team arrives. As he sits back to wait, he notices something emerging from the ceiling...

Ryan is enjoying basketball with his friends and catching up with them because of his various absences. As he is talking to one friend in particular, Ryan spots a car with two men standing at each side, waiting for him.

Yaz is about to embark on her fourth "secondment", much to the concern of her mother and her police superior. Her gaze is then drawn to two men waiting by a car.

Graham is being told the results of his medical tests. Everything is all clear, but when he leaves the hospital he is greeted by men with a car.

The Doctor is working on the TARDIS when a group of cars and men arrive. Uniting the four travellers, the cars are to escort them to an important meeting. En route to their secret destination though, the satnav kills the driver and keeps repeating a simple message: "DIE". The car then begins to drive by ltself, reversing fast through oncoming traffic.

• Jodie Whitaker (The Doctor)
• Bradley Walsh (Graham O'Brien)
• Mandip Gill (Yasmin Khan)
• Tosin Cole (Ryan Sinclair)
• Laura Fraser (Kane)
• Gia Re (Bella)
• James Buckley (Nevi)
• Julia Foster (Vilma)
• Amy Booth-Steel (Hyph3n)
• Will Austin (Vorm)
• Col Farrell (Benni)
• Lewin Lloyd (Sylas)
• Spencer Wilding (Lead Dreg & creature movement)

Graham has been collecting coupons and has now collected the required number for a free holiday on Tranquility Spa. As he assembles a cube from the coupons the Doctor tries to warn him, but too late as seconds later all four of them are transported to their holiday destination. The travellers are greeted and welcomed by Hyph3n who responds to the Doctor's query about returning to the TARDIS: they can return at anytime - but they are booked in for a two-week vacation. Yaz heads off to find the pool, Ryan decides to check out the building and Graham maps out his day: sit down for three hours, get up and move to another seat and then cocktails. The Doctor decides to have a look around.

An alert is picked up and someone goes off to investigate. It is not long before other problems begin to assail the spa. So much for the vacation.

• Jodie Whitaker (The Doctor)
• Bradley Walsh (Graham O'Brien)
• Mandip Gill (Yasmin Khan)
• Tosin Cole (Ryan Sinclair)
• Goran Visnjic (Nikola Tesla)
• Robert Glenister (Thomas Edison)
• Anjli Mohindra (Queen Skithra)
• Haley McGee (Dorothy Skerritt)
• Paul Kasey (Harold Green)
• Robin Gulver (Bill Tallow)
• Erick Hayden (Mr Sorensson)
• Russell Bentley (Mr Brady)
• Brian Caspe (Mr Martin)
• Shaun Mason (Foreman)

Nikola Tesla is at Niagra Falls, presenting a proposal to would be investors: a world wireless system that will deliver power to every corner of the Earth. As he asks for an investment of $50,000 the would be investers feel that not only is the amount a great sum, they are also concerned about electricity travelling through the air. One investors remarks on it being akin to the notion of people on Mars. Tesla's reply that he has been receiving signals from Mars only serves to distance him from the investors and then the lights flicker, belying his statement that his facility is reliable, and a man is found dead, apparently electrocuted. His assistant, Miss Skerritt suggests that Tesla has nothing to hide and he announces he will investigate by himself.

Tesla believes he has found the problem when he notices a glowing sphere. Miss Skerritt asks him what it is but he has no answer. Hearing a noise, the two of them set off to find the source. And then the Doctor bursts through a door: she is searching for the source of a mystery energy signal.

• Jodie Whitaker (The Doctor)
• Bradley Walsh (Graham O'Brien)
• Mandip Gill (Yasmin Khan)
• Tosin Cole (Ryan Sinclair)
• Jo Martin (Ruth Clayton)
• Neil Stuke (Lee Clayton)
• John Barrowman (Captain Jack Harkness)
• Ritu Arya (Gat)
• Paul Kasey (Judoon Captain Pol-Kon-Don)
• Nick Briggs (voice of Judoon Captain)
• Simon Carew, Richard Highgate, Richard Price & Matthew Rohman (Judoon)
• Michael Begley ("All Ears" Allan)
• Judith Street (Marcia)
• Katie Luckins (tourist)

Ruth Clayton makes her own breakfast: Lee had intended to but he was still asleep when she got up. Ruth reminds him that she doesn't want any presents for her birthday, just a cake. Then she sets off for her job, a tour guide to the sights of Gloucester. Except that no one seems interested in a guided tour. Rutg goes to a cafe to get a cup of coffe. The owner, Allan makes it clear he has feelings for Ruth and suggests that her husband, Lee is no good for her. Allan has his own dossier on Lee which he tries to interest Ruth in. She leaves the cafe.

A Judoon ship is in orbit around Earth: their detectors have picked up their target. As the Doctor ponders over other matters, her attention is distracted by an alert from the Judoon ship. There is a zonal restriction around Earth and they will be sending down a platoon - to Gloucester. The Doctor intends to slip through the barrier: while the Judoon may be police, they are trigger-happy police. Ruth watches as various people are checked. When an older woman, Marica challenges the Judoon she is killed: they intend to catalogue everyone within the zone in search of a fugitive.

• Jodie Whitaker (The Doctor)
• Bradley Walsh (Graham O'Brien)
• Mandip Gill (Yasmin Khan)
• Tosin Cole (Ryan Sinclair)
• Warren Brown (Jake Willis)
• Matthew McNulty (Adam Lang)
• Joana Borja (Gabriela Camara)
• Molly Harris (Suki Cheng)
• Gabriela Tolol (Jamila Velez)
• Soo Drouet (Joyce)
• Tristan de Beer (Zach Olson)
• Thapelo Maropefela (Aramu)

A space capsule is plunging back towards Earth: the automatic systems have failed. Ground control suggests switching to a ballistic descent and maintaining trajectory, but the astronaut, Adam Lang replies that he is way off course.

Former police officer, Jake Willis, rugby-tackles a shoplifter in a grocery store, much to the annoyance of the manager. Jake heads off to a bar for a drink or two. There he sees the news announcement that Lang's capsule has crashed. off him there is no trace so he is missing, presumed dead. Then Jack receives a series of texts, allegedly from Adam...in Hong Kong.

In peru, two women arrive at what is mean to the most beautiful river in the world only to find the banks strewn with letter. Overhead birds are circling and squawking. Jamila and Gabriela end up camping there overnight, Jamila, unable to sleep hears noises outside the tent and goes to investigate. She is attacked and in the morning Gabriela awakens and tries to find Jamila. A bird drops out of the sky but before she can pick it up, Ryan appears on the scenes and warns her not to touch it.

• Jodie Whitaker (The Doctor)
• Bradley Walsh (Graham O'Brien)
• Mandip Gill (Yasmin Khan)
• Tosin Cole (Ryan Sinclair)
• Ian Gelder (Zellin)
• Buom Tihngang (Tibo)
• Clare-Hope Ashitey (Rakaya)
• Bhavnisha Parmar (Sonya Khan)
• Aruhan Galieva (Tahira)
• Sirine Saba (Maryam)
• Nasreen Hussain (Anita Patel)
• Everal A Walsh (Gabriel)
• Michael Keane (Fred)
• Amanda Liberman (mum)
• Willie Jonah (old Tibo)
• Anthony Taylor (Andrew)

In Allepo, Syria in the year 1380, Tahira runs from a man accusing her of theft. She returns to the hospital where she is currently residing. With the doors locked she asks Maryam to make sure that before evening all the doors must be locked and all the precautions taken. Maryam tries to assure Tahira that her fears may seem real but they are only in her mind, but Tahira insists they are real. When night falls, Tahira approaches Maryam and asks why the doors are not locked. Maryam tells her that it is not done but then Tahira remarks that it is too late.

The Doctor returns her three friends to Sheffield, albeit 77 minutes later than the intended time. While Yaz, Graham and Ryan go to their respective homes, the Doctor states she will carry out some maintenance, deal with correspondence etc - and they can all meet again tomorrow lunchtime. Alone, the Doctor ponders for a second if she should go somewhere but decides she will just travel forward to tomorrow lunchtime. The TARDIS lights dim for a few seconds, focussing the Doctor's attention on an alert. Someone appears inside the TARDIS, departing as quickly as he arrived without the Doctor noticing. The TARDIS locates activity in Aleppo, 1380 and so the Doctor sets off to have a look.

• Jodie Whitaker (The Doctor)
• Bradley Walsh (Graham O'Brien)
• Mandip Gill (Yasmin Khan)
• Tosin Cole (Ryan Sinclair)
• Lili Miller (Mary Wollstonecraft Godwin)
• Nadia Parkes (Claire Clairmont)
• Jacob Collins-Levy (Lord Byron)
• Maxim Baldry (Dr John Polidori)
• Lewis Rainer (Percy Bysshe Shelley)
• Sarah Peries (Elise)
• Stefan Bednarczyk (Fletcher)
• Patrick O'Kane (Ashad)

By the shores of Lake Geneva in June 1816, a group of people comment that once again they are indoors by a storm. As the guests discuss what to do, it is suggested that stories to awaken thrilling horror might be told. Byron picks up a book that he belives is the very thing: Tales of the Dead. As he begins to read a story, someone knocks at the door. Mrs Shelley wonders if it might the death-bride from the very story they are listening to. Byron remarks that he should be the one to greet it. Responding to his challenge as to who will accompany, they all go to answer the door. They are faced with four travellers: the Doctor, Graham, Ryan and Yaz.

After they have been invited in, the travellers leave their outer clothing to dry. Again the Doctor suggests that they only stay for an hour or at least until their clothes have dried. Yaz is excited that they are here with Mary Shelley, on the night in which she would be inspired to write Frankenstein

• Jodie Whitaker (The Doctor)
• Bradley Walsh (Graham O'Brien)
• Mandip Gill (Yasmin Khan)
• Tosin Cole (Ryan Sinclair)
• Patrick O'Kane (Ashad)
• Julie Graham (Ravio)
• Ian McElhinney (Ko Sharmus)
• Alex Austin (Yedlarmi)
• Steve Toussaint (Feekat)
• Rhiannon Clements (Bescot)
• Matt Carver (Ethan)
• Jack Osborn (Fuskle)
• Evan McCabe (Brendan)
• Branwell Donaghey (Patrick)
• Orla O'Rourke (Meg)
• Andrew Macklin (Michael)
• Caolan Byrne (Sergeant)
• Sacha Dhawan (The Master)
• Nicholas Briggs (voice of the Cybermen)
• Matthew Rohman, Simon Carew, John Davey, Richard Highgate, Richard Price, Mickey Lewis, Matthew Doman, Paul Bailey (Cybermen)
• Seylan Baxter (Tecteun)
• Kirsty Besterman (Solpado)

A man is cycling along when he comes across a baby in a basket in the middle of the road. The police will try to find his parents, in the meantime the man and his wife will look after the baby. As time passes the baby grows up and the man and woman are officially made his parents.

Using the co-ordinates provided to her, the Doctor has brought Graham, Ryan and Yaz with her to a planet in the far future to a time after the Cyberwars when the majority of the human race has been wiped out. Below them is a settlement of seven people, probably the last remaining humans. Two Cybermen spaceships arrive, so the settlers realise that there is nowhere safe from the Cybermen. The Doctor and friends arrive, with some devices that will assist in defending the settlement from the Cybermen. The settlers have no weapons, they are not soldiers, merely refugees constantly fleeing the Cybermen. Cyber drones arrive, targeting the defences. The battle has begun.