Producer David Richardson said: "From the very first scene, we're thrown into something very different – a dark story in which two agents are on the trail of a killer, in a place that is familiar but so very different. It's a tale packed with surprises and left turns, as Alfie throws everything into this brilliantly conceived Time War story."

Writer Alfie Shaw added: "When Matt Fitton asked if I wanted to do a War Doctor box set, I’d just finished doing a war against the Daleks box set for The Eleventh Doctor Chronicles, so I wanted to do something completely different. There are no Daleks and no massive space battles in Fallen Heroes. It’s a little backwater town on a backwater planet that’s about to be messed up by the greater conflict. 

"The inspiration for this set was stuff like True Detective and Alan Wake 2. Yes, there’s a murder to be solved, but the focus is more on how the crime affects those caught up in it rather than a Christie-style whodunnit. I really wanted it to almost not be Doctor Who, and the fact it must become Doctor Who again is part of what messes things up for everyone. 

"It’s weird – possibly the weirdest one I’ve done – but if you're doing a whole box set in the Time War, you need to take a big, bizarre swing. I adore Daisy and Jonathon and have wanted to work with them both on something for ages. I’m over the moon that we were able to make it happen for this one."

Jonathon Carley said: "Working with Daisy has been a delight! To be able to not only work together, but to play some different characters, and work on a different dynamic in our buddy cop situation. We’ve just absolutely clicked. 

"A big thing that’s run through all of the War Doctor sets has been the idea of identities, and in this one, it's on a different scale. Wyatt Smith is the Doctor, or is the Doctor Wyatt Smith? So there've been great opportunities and challenges in developing new directions and new spins on the characters. I’ve loved every moment of this one." 

His co-star Daisy Ashford added: "The script is mad - I thought it was very complicated and brilliant. Louisa Tickson is quite no nonsense, a go-getter. She's very much got echoes of Liz Shaw in there! 

"I’ve known Jonathon Carley for a long time, but I've never had the chance to work with him, and that's been a real treat. He's brilliant. It's the first time I’ve been in a room with him doing John Hurt, and it is extraordinary. You can shut your eyes and he's there."

Jonathon Carley and Daisy Ashford

Alfie Shaw, Daisy Ashford, Christopher Naylor, Jonathon Carley, Kerrie Taylor, Maria Teresa Creasey, David Richardson, Ken Bentley

Alfie Shaw, Daisy Ashford, Christopher Naylor, Jonathon Carley, Kerrie Taylor, Maria Teresa Creasey, David Richardson, Ken Bentle

LtoR David Richardson, Christopher Naylor, Vineeta Rishi, Paul Panting, Alfie Shaw, Ken Bentley, Iain Conningham, Maria Teresa Creasey, Jonathon Carley