BBC One’s cold cases crime drama Waking The Dead returns next week for a ninth and final series. Tara Fitzgerald has played Eve Lockhart since she joined the cast in 2007.

As the team’s forensic pathologist, Eve is hardworking and married to the job. Before working with the Cold Case Unit, Eve excavated mass graves in Bosnia and Sri Lanka which has led her to pioneer the UK’s only ‘Body Farm’. This comparative bone bank is her unique archive: thousands of bones and skulls testify to the rich variety of death, disease and dismemberment. A brilliant scientist at the cutting edge of DNA and new technologies, Eve’s well versed in skeletal and decomposition expertise, forensic toxicology and pre and post mortem injuries.

> Order the Series 9 boxset on Amazon.

> Order the Complete Series 1-9 boxset on Amazon.

How did your role in Waking The Dead initially come about?

“It came about in an orthodox manner, in as much as I just had a call to go in and meet. I went in to meet the team, then read with Trevor Eve. That went really well, I liked him very much, and was then offered the role.”

What have you found most interesting about playing a forensic scientist?

“I didn’t know anything about it, so I found it fascinating just what they can discover from what might appear from the outside to be the most unlikely of sources. For example: from insect predation on a body, you can discover the place of death – i.e. the corpse might have been moved and the time that has elapsed since death. Then there are the discoveries of things like pollen and different seeds that can inform them as to the whereabouts of the murder or suicide.

“Also what ‘phase’ the body is in can be determined because the maggots develop, hatch and turn to flies, sometimes you even get a second wave of maggots. So they can work out what phase it is, whether the first or second, and it is extraordinary.

“It is developing still ever further and that’s where technology is so helpful because they are able to go into more detail. They can compare their notes with research facilities in other countries to learn about how the same insects in different countries produce different results.”

What is your favourite memory from working on Waking The Dead?

“It’s so hard, there’s been so many! The whole experience was good because I learnt so much. Not only in terms of being an actress from working with such good actors, but also the field of expertise is so rich and there have been such good available specialists to help with that.”

What is your favourite moment from working on the series?

“I think it was at the beginning of the last series, when we all had to come together to search for Eve’s escaped lab rat. When we were doing it, it struck me as a slightly surreal and funny thing to be doing, running around the office looking for an escaped rat.

“And also in another episode, I think ‘Magdalene 26’, they had made this amazing body which was strung up and the eye sockets were filled with maggots, all the sockets actually were teaming with maggots. But when they settled down all the maggots were completely still and you couldn’t really see them.

“I went towards the hanging corpse and gently prodded the eye socket and suddenly all of these maggots began to crawl. That stayed with me. What’s strange is, I’m actually in life quite squeamish, but when I’m doing things like that I’m strangely not.”

Which guest star have you enjoyed working with the most and why?

“That’s very difficult to answer as we have had the top end of British actors throughout the series. My character Eve interestingly doesn’t have that much to do with the guest stars because she is very isolated in a way. But working with Joseph Mawle again, he is such a fine actor, so that was such a good opportunity.

“And I really enjoyed Dr Andy Hart, the forensic etymologist, who was advisor on the series. He and I did a small scene together just out in the fields, and I really enjoyed that. He was so good, a complete natural.

“He was asked if he could think of something to talk about, as if we were discussing a case, and he was able to ad-lib very naturally. That was great, I loved that. It was slightly disconcerting how well he did because I don’t think if we were to reverse roles I wouldn’t be as good an etymologist!”

What has been your favourite episode and why?

“They all were for different reasons. However, there were two I really enjoyed especially – episodes where Eve was involved in the case. One was ‘Pieta’, which Philippa Langdale directed – it was a subject area which interested me, the Bosnian war and the excavation of mass graves, and again what happened in Sarajevo. Around that time I found it both interesting and tragic, it was also very moving because there was the discovery of a mother holding her young son.

“The other episode is ‘Substitute’ – the one I did with Joseph Mawle. Because again there was more for Eve, she had a love interest, so there was an extra dimension to the story for her.”

How have you found working together representing a Cold Case Unit, off screen?

“It’s hard when you’ve been doing something for a while because on-screen and off-screen sort of fuse into one another. I really respect the actors, I have great respect for Trevor and Sue and Wil and Eva and Felicity and the others I have worked with, and the process that we would go through when we were filming was really helpful.

“We really talked all the scenes through and made sure that we were clear on our attitudes and what position our characters were coming from so it never felt dry. There was always either an emotional or intellectual connection to what we were saying. But that was very much established by the time I had arrived, this very strong working method which I had never had any experience of any where else.

“I thought that was very valuable, and each episode felt like a film, a story unto itself. They are such good actors, it makes it easy.”

Which stunt have you found most challenging?

“The term stunt is used to cover a lot of things, including me jumping off of the side of a desk, which I didn’t really think of as a stunt. But going in the cold water – for Series 8 in an episode called ‘Substitute’ – did feel like a stunt. I’m not very good with cold, and it was so cold ice had been on top of the lake earlier in the day, but then it did create this beautiful scene, so it was worth it.”

Is there a prop or item of clothing that really helped you get into character?

“It would have to be the lab coat. When I put on one I automatically feel something, somehow official and in a clean zone. I also had another suit, which was sort of an all in one suit. I really liked the juxtaposition of the two. They were both sides of Eve’s character.

“One that she would get very dirty down on her hands and knees in some godforsaken place, and then cleaned up really well when she had to be in her lab. They are almost like the two sides of what the character does. Out in the fields and in the lab.”

Eva Birthistle joins the cast this series. How does your character react to her joining the Cold Case Unit?

“Some of it I don’t know, because I don’t know how it will play out in a way. I felt there was initially some suspicion about how it was going to work. Because she is in quite a senior position so in a way the most challenging to Boyd.

“With Boyd being such an alpha male, I think Eve wondered how he was going to react to the threat. But then very quickly that changes to one of deep respect and admiration because inevitably, a fellow female, in a place that is predominantly male, or certainly still has very male attitudes intrinsically. There is admiration for any woman who can reach a senior position in that, and doesn’t play the feminine card.”

What will her character bring to this series?

“A new area of expertise, her experience in counter terrorism and also some humour. That is what is laced through this series, the humour, which was always something that is evident on set. It was a very enjoyable place to be, you always felt a laugh wasn’t that far away, it was always just round the corner.

“When you are dealing with such heavy, brutal information it is needed. A necessary relief because you have to take things incredibly seriously and given them the correct weight, and then you have to sort of have this valve to let off. So she brought that, and an intelligence and commitment to the work.”