I was delighted when John Ainsworth asked me to write a Dalek story for Colin and Nicola for the monthly range. It seemed like a natural successor to my last monthly range script, Hour of the Cybermen, which had Ol’ Sixie pitched against his other arch enemies from way back.

I was given a wide brief, any setting I liked, and I went for an off-Earth story which has its basis in a tactic of the Persian Empire. They would conquer a territory then put a plenipotentiary or emissary in place as its ruler. The population would be treated relatively well, on condition that there were no attempts at rebellion. If there were, the Persians would return and be totally merciless in not just quelling the rebellion but taking cruel revenge on the population. It was a very successful tactic in keeping conquered cities in line. So I envisaged a world taken over by the Daleks with one of these emissaries in charge. An emissary with the principle objective of ensuring there’s no dissent. Because if there is, the Dalek reprisal will be terrible. And what would the Doctor and Peri do, coming into this setup? Would the Doctor want - or be able - to quell his usual instinct to foment rebellion and overturn Dalek rule?

I’d written Daleks before, for the War Doctor range, and found them great fun to do. This was my first time telling a standalone Dalek story of this length, and again it was a treat. It’s just not possible to write ‘Exterminate!’ without smiling. Even more of a treat is writing for Colin. I’ve written four or five stories for him now, and I just love his Doctor and what he does with him in the studio. To get to write for him and Nicola again, my first Sixie and Peri adventure since The First Sontarans in 2012, was the icing on the writing cake.

The Daleks are iconic of course, and were a highlight of my Doctor Who viewing as a child. I particularly remember 9-year- old me’s excited anticipation of their return in Day of the Daleks after an absence of many years. That remains one of my top favourite Doctor Who stories. It’s also one that, like Emissary, features a representative of the Daleks, the Controller, running a totalitarian state in their name. Which provides a satisfying if tenuous link to my story, while also setting a precedent for the use of this tactic by the Daleks.

London, 1952, and a deadly smog envelops the capital. But something even more dangerous – and alien – is hiding within the mists. When the Doctor and Donna get lost in the fog, they find a motley group of Londoners trying to make their way home. Soon the stakes are raised as death creeps along fume-choked streets, and not everyone will make it out alive...

Being asked to write for David Tennant and Catherine Tate was already a huge thrill, but how awesome to hear The Creeping Death will be getting a vinyl release too! I think this nineteen-fifties tale of a band of London misfits against whatever-it-is that lurks in the smog will work beautifully on a neon green LP!

I’m a big vinyl fan already – I share my flat with three record decks, goodness knows how many records, and one long-suffering partner – so I’m super-eager to get my hands on a copy!

As we had such a great time doing the first volume it seemed a lovely idea to do another. Amazingly, John managed to find time for us AND capture a nation’s heart in the jungle. Hearing him face off against Colin Baker’s Doctor is the joy we’ve all been waiting for.

I love an adventure where we interfere with history, especially when we completely destroy the reputation of a historical character! My Doctor travelled to The Great Fire of London, then the destruction of the dinosaurs… everything in history is handed down to us.

I think all our heroes of history would be disappointments if we actually met them! Plus, I was ‘fanboying’ over Dirk Gently which Samuel starred in.

There is a precedent in Doctor Who of the Doctor visiting real life occasions, locations and people that are familiar to us in history. The Doctor meeting Cicero lets us see Cicero’s skills as an orator that will hopefully help to save the day… Peter Davison’s portrayal of the Doctor was my Doctor on television when I was growing up, so I’m absolutely thrilled.

Day of the Master was possibly the most exciting and yet terrifying brief I’ve ever had. Finishing off the Ravenous arc was a big enough responsibility on its own... but throw in wanting to give great material to Sir Derek Jacobi... and Michelle Gomez... and that’s before we even get to the heart-stoppingly fantastic prospect of bringing Eric Roberts’ Master back face to face with the Doctor again for the first time in over twenty years.

Well, you can see why it might be intimidating! But honestly, it was one of the best times I’ve ever had writing a Doctor Who story. I really hope the audience enjoy it as much as I did!

We’ve tried to do something a bit different with Ravenous. Coming out of Doom Coalition, we wanted to go a bit darker, a bit scarier – to mark the saga with a shift in tone. With all four box sets now recorded, I feel a sense of relief – it’s been such a huge logistical challenge! Ravenous 4 alone required six studio days in cities as far apart as Los Angeles, New York and London! But we did it. We told that whole, big story and we’ve brought back three Masters and Missy in a breathtaking finale.

It was a real thrill to bring Geoffrey Beevers into our Eighth Doctor Adventures, doing what he does best in Planet of Dust - subjugating an alien world, and then setting about a chain of events that will drive our Ravenous story forward.

I’m really proud of it – and yet I don’t really have much time to stop and think about it because we’re already onto the next chapter for the Eighth Doctor! And life is going to be very different for him and his companions

This seems to have been a box set for reunions. It’s going to be fascinating to hear what listeners think of the Eighth Doctor reuniting with Roberts’ Master. I’m sure those shockwaves will ripple through time. But it was a genuine delight to have Nicola Walker reunite with Derek Jacobi. The green room was filled with laughter that day.

When Zoe reattaches an old piece of equipment to the TARDIS console, she, Jamie and the Doctor are very lucky to avoid a collision. But the place they find themselves in may be even more dangerous - because there they encounter another Doctor, a space pilot called Steven... and a young woman called Katarina who really shouldn’t be there.

From the beginning, I had so many exciting elements to play with. Contrasting the fun and frolics of the Troughton years with the darker days of the late Hartnell era was something I wanted to get my teeth into, with the Daleks providing their customary threat.

However, I always knew what the core of my story should be. What could possibly bring the two Doctors into conflict, on the opposite sides of a dilemma?

It could only be the fate of Katarina.

It’s the middle of the Second World War and Ben Jackson has returned to visit his married friends Polly and Jamie in their quiet English village. But they can’t quite shake the feeling that something’s not right.

I found out that when the first episode of Dad’s Army went out in 1968, James Beck (playing dodgy dealer Walker) invited a good friend round to watch it, and that good friend was Doctor Who story editor and writer David Whitaker. It was roughly around the time Whitaker was working on The Enemy of the World and The Wheel in Space, and so I started to think about how you’d do a Dad’s Army kind of Doctor Who story with that kind of baroque, complicated plotting.

This incarnation of the Master is very much the ‘Hannibal Lecter’ of Time Lords – intelligent, charming, but thoroughly ruthless. We had a lot of fun in studio bringing the War Master back to life! It’s been a gift of a project, and we can’t wait for listeners to hear it.”

Sir Derek was only seen on screen for one TV episode. On returning to the role on audio in 2017, he said: “I didn’t expect to come back to it all these years later but I was thrilled to be remembered. The plots in all these episodes have been very good indeed, very interesting, very dramatic and beautifully written. The whole process has been a delight!

Doing The Death of Captain Jack was incredible! I have missed doing Torchwood so much. Beyond being proud of playing a part in it, the character itself is a blast to play, and those two episodes just weren’t enough.

Writing The Death of Captain Jack was a total blast, and both James Goss (producer of the Torchwood range) and I realised we could have a lot more fun with Captain John Hart, providing James Marsters was happy to return.

Captain John is this chaotic, disruptive, insubordinate force of nature; completely amoral and unpredictable, so that gave me a lot of freedom! Writing is often a case of knowing when to hold back, when to tread a more subtle line, but with Captain John it’s the complete opposite. And setting it before Torchwood on television meant we were able to go to places where Torchwood can’t.

I approached Russell T Davies with the idea of Big Finish making a Rose Tyler spin-off. He was very enthusiastic - as always - and suggested we followed Rose’s journey that ultimately leads to her finding the Doctor in The Stolen Earth. I found the pro-posal irresistible, and instantly script editor Matt Fitton and I were throwing around ideas. There is a whole multiverse of possibilities. Russell suggested including Jackie and Pete, and embraced my idea of including a parallel universe version of Clive - who of course was killed off in the TV series (in the 2005 episode Rose).

Russell guided us gently through the development - steering us towards ideas that worked brilliant-ly, ensuring things that needed improvement were fixed, and also throwing out the ideas that didn’t work. I’m absolutely delighted with what we have - a family drama about the end of worlds. It’s about love and loss and things that might have been - and our brilliant cast have embraced the emo-tional scripts.

What we have is different from previous iterations. It’s rather dark (though never short on wit and charm) but it’s not really about villains. It focuses on the fight to survive against the odds, and on the power of family and love.

I love how normal Rose is, and yet really extraordinary. She lived a normal av-erage life but she is incredibly curious and has an enormous capacity for love and empathy and is really spirited. She is extraordinary.

That’s the great thing about Doctor Who. It challenges new-thinking. It’s progressive and it can be political in amongst these human emotions and relationships. I think that’s its greatest appeal.