Endeavour's Shaun Evans and Roger Allam break down the show's emotional series finale

Endeavour series finale spoilers follow.

Eleven years and 35 episodes since its launch, Endeavour has finally come to an end with a feature-length finale (series nine, episode three) that not only brings the long-running mystery show to a satisfying close but also includes a tear-jerking nod to the original Inspector Morse series that it was a prequel to.

If you've already watched the final episode — entitled 'Exeunt', the stage direction that tells more than one actor to leave the stage (in case you weren't sobbing enough already — put the crossword to one side, grab a whiskey and read on as Digital Spy exclusively chats to Shaun Evans and Roger Allam about saying a last goodbye to Endeavour Morse and Fred Thursday.

And if you haven't seen 'Exeunt' yet, don't say we didn't warn you: There are some major, considerable and even humongous Endeavour finale spoilers ahead.

Have you known for a long time how Endeavour would end?

ROGER: It's often been raised how it would end. How can it be explained that Endeavour — well, John Thaw's Inspector Morse — never mentioned a man called Fred Thursday? Various ideas were floated. I think it was a couple of years ago that Russ [series writer Russell Lewis] came up with the one that we've got now. The endpoint, the very ending of it.

SHAUN: We've been having conversations for years. All of us put our two-penn'orth in. Rightly so, you know — we're all invested in these characters and these stories, I think it was important for all of us.

We know Endeavour becomes John Thaw's Inspector Morse, but as Thursday is never mentioned in that series, anything could have happened to him. Did you want him to die tragically at the end?

ROGER: At one point, I did want to die in a blaze of glory, fighting off all the bad guys! But I knew that wouldn't work — because then, why would Morse never mention Fred Thursday? Also, I can see how it might overbalance the story because a lot of the regular characters' stories have to be dealt with. I think I really do like it [the ending Thursday gets]. I think it's very good.

Were you sad during filming, knowing it was the final series?

SHAUN: I can't speak for everyone else, but there was a sense on set that it was the right time for all of us to call it a day, you know?

Of course, you're often nostalgic, knowing this is the last time we will do things, but everything reaches its natural end. You have to respect that. It did feel different, but also kind of richer because of it. Because you know we won't be doing this again. We won't be having any more scenes like this together.

For example, with Endeavour and Joan, this is what we've been driving towards. With me and Thursday, this is what it's all been for — to celebrate this moment, and the passing of it. And that's great for an actor, that you're driving towards something. It did feel different — but different in a good way.

ROGER: It became so [sad] when you got to the last scene in a particular set, like the last scene in my house, which I have to say I wasn't sorry to see go. It was just a horrible set — really difficult to film in and very small for the crew and camera. And it got really, really hot.

But it was terribly emotional doing the last scene with Caroline [O'Neill] in that set, or with Anton [Lesser] in his office, you know. Previous to Endeavour, I had been hugely suspicious of getting trapped in a long-running series, but what's lovely about it is the group of people that develops and becomes a company of actors. That's most of all what I miss, that group of people.

How did you feel when it came close to the end?

SHAUN: The last few scenes felt like a celebration. You can't keep doing the same thing and having the same conversations, you know. What felt particularly beautiful and poignant about the filming of this whole season was like: 'Wow, we've had the opportunity to do this so many times, and look into each other's eyes and say our lines and do our work together. And hasn't that been a privilege?'

But you know, a lot of the arcs of the characters are coming to a conclusion in this and so you realise that's what you've been driving towards. And what a blessing it's been.

ROGER: We were invited to go down to the last day of recording the music in a studio in Hampstead and I've never done that before. I went along and it was incredible. I mean, they had something like a 50-piece orchestra, a full orchestra, and to hear Barrington's [composer Barrington Pheloung] music done for the final credits, for the last time, live in the room with this big orchestra, was just fantastic.

A scene near the end will have fans crying — at Joan's wedding, Endeavour finally tells her how he feels, only for it to be revealed that he's imagined it and didn’t say it out loud. Can you talk about that?

SHAUN: I felt that was really important. It's kind of unusual that we broke the language of the stories by seeing inside someone's mind. It was important to get those words out and for these men — a stratospheric generalisation here — who don't say what they feel at the time, it's important, and it's important for the audience, but also for him as well in that moment of dawning: 'No, f**k, this is what I want, if only I could have said it.'

That moment, and the inability to say it, will haunt him for the rest of his days, I think.

There were so many conversations about the scene, and then in the final edits it was in, and then it was out, and it was in, and then it was out, and I just felt really strongly that it would be less if the scene wasn't left in.

The final scene has Endeavour in his black Jaguar, driving away from Blenheim Palace. He passes a red Jag going the other way, and we see older Morse's (John Thaw) eyes in the rearview mirror. Was that the last scene you filmed?

SHAUN: Yes — it worked out perfect, actually, as that last day I was alone. We had a slightly reduced crew and it was a lot of driving scenes with me in the Jag. I was the only actor in on that day.

We went to Blenheim Palace and drove it down, and we were trying to get a particular shot with this drone. So there was a lot of up and down the same road as the sun was disappearing over the hills of Blenheim. I was in the car and I thought: 'Yeah, I think I'm done with this now.'

It was an amazing moment, personally, to slowly say goodbye.

Endeavour series 1-9 and Inspector Morse series 1-8 are available to stream on ITVX.

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