In episode five, the Doctor continues in his quest to defeat the evil Sontarans
The Sontarans are trying to take over the world by turning cars into killing machines
There’s big trouble ahead – Martha has been cloned and is now helping the Sontarans
With Donna’s help, the Doctor tries to stop the Sontarans – and Martha – in their tracks
But Donna soon finds herself under threat from the enemy…
In episode four, Martha Jones contacts the Doctor – she desperately needs his help…
Martha now works for alien defence team UNIT – and she must battle the evil Sontarans
General Staal (Christopher Ryan) leads the Sontarans, whose mission is to conquer the world
Can the Doctor fight the Sontaran invasion?
Martha Jones, the Doctor and Donna meet Sontaran Commander Skorr
The Sontarans will stop at nothing to achieve global domination
One of the deadly Sontarans – up close and personal
The Doctor discovers the Sontarans’ next move…
It’s a race against time – can the Doctor and Donna stop the Sontarans in their tracks?
In episode three, Planet of the Ood, the Doctor travels to the future and lands on the Ood-Sphere…
The Doctor’s sidekick Donna is surprised to meet the Ood race for the first time
The Ood is definitely a scary-looking creature…
…But is it the Doctor’s friend or foe?
The Doctor has spotted something in the snow…
It’s one of the icy planet’s many inhabitants, the Ood
The Doctor and Donna go to rescue the defenceless alien
The Doctor soon meets Dr Ryder…
…And his sidekick Mr Halpen
But what do they know about the Ood race?
Halpen and Ryder consider what to do with the creature
Deep inside the Ood-Sphere, the Doctor and Donna find the Ood struggling for survival
The Doctor discovers why the Ood would want to be a servant race
Donna is disturbed by what she sees
‘Donna, we must save them!’
Can the Doctor and Donna rescue the Ood before a powerful secret destroys them all?
When in Rome, dress as the Romans do… Donna goes with the flowing look
The Doctor and Donna in a street scene from The Fires of Pompeii
Comic actor Peter Capaldi plays Caecilius
Phil Davis stars as Lucius
Former Stella Street star Phil Cornwall plays a stallholder
Karen Gillan plays the enigmatic Soothsayer
They look like any young couple on holiday in Italy…
So what makes them suddenly take to their feet?!
It’s certainly alarming Caecilius and Metella (Tracy Childs)
The stallholder looks none too happy either
He came, he saw, he conquered… Eventually! Watch Doctor Who on BBC1 on Saturday, April 12
Previously on Doctor Who… the Doctor and Donna reunite to take on ‘Miss Foster’ in episode one
David Tennant plays the Doctor, Catherine Tate plays Donna and an old police box plays the TARDIS
Filming behind the scenes in Rome for the second episode, Fires of Pompei
Donna and the Doctor with Martha, who returns later in the series, and Sontaran commander Skorr
Director James Strong issues some instructions on set
Who’s behind the sinister company, Adipose Industries?
It’s Sarah Lancashire as Miss Foster
Who are you calling Anne Robinson!
Jacqueline King plays Donna’s mother, Sylvia
What on Earth is happening in London in episode one?!
Bet it has something to do with the iron lady
Now… you just hold on there! The Doctor tries diplomacy
The Doctor appears to be hypnotising himself
There are always fireworks when Donna’s around
The Doctor wields his sonic screwdriver
For something completely different, the duo in this week’s TV & Satellite Week (photo: Dan Goldsmith)
Don’t touch that remote control! I’m back on BBC One on Saturdays (photo: Dan Goldsmith)