Dalgliesh teases romance for lead detective with introduction of Emma Lavenham

But his suggestions were met with some resistance, and a short time later, he was found dead in the chapel.

Crampton had arrived with Dr Emma Lavenham, an art professor from an auction house in London. She was there to assess The Doom ahead of the proposed sale, and was staying at the school the night he was killed.

Naturally, her proximity to the case required that she be interviewed by Dalgliesh, but he quickly arrived at the conclusion that she was not a suspect.

As a result, their dynamic took on a different shape, the detective's brooding intensity clearly making quite the impression on her.

Read more:

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Following another death, that of Agatha Betterton, who was found at the bottom of some stairs, Dalgliesh and Tarrant were once again required to collect witness statements from everyone, including Emma.

But this time, it was the latter who spoke to her.

"Oh," she said, visibly disappointed when opening her door to find Tarrant standing before her, rather than his superior.

But later that day, they did cross paths once again, this time in the chapel, where they discussed their respective views on religion and spirituality – and shared some teasing prolonged eye contact.

Dalgliesh, who so rarely opens up to anyone, found himself drawn to Emma, and their final encounter, although brief, promised more to come.

"Hopefully you won't have to give evidence to trial," he said after discussing the case's conclusion, which saw George Gregory unmasked as the killer.

"I'd cope, if you were there," she added, before giving him her card.

"In case you need me."

Emma isn't set to feature until the final part of season 3, but fans of PD James's books will know that she does start dating Dalgliesh, although they aren't always able to commit to their plans on account of his demanding police work - which does create tension.

However, they do eventually find their feet as a couple, and go on to get married in James's final novel, The Private Patient.

Speaking ahead of the season 3 premiere, Bertie Carvel explained how Dalgliesh's former work partner, newly promoted DCI Kate Miskin, who is set to reappear this season, is "key" to his new relationship.

"She unlocks the growth that has been waiting to happen throughout these whole three seasons," he said. "He's moved in various different directions in terms of his secret heart, and she kind of holds the key in a funny kind of way.

"PD James had this great phrase about Dalgliesh having a sliver of ice in the heart, and I think she was talking about his ruthlessness more than anything else.

"But also, I think about that in terms of his wound and the grief, which is where we’ve started him with this series, and that actually the slow thawing of that sliver of ice is what's been happening for these three years."

Carvel continued: "A huge part of that is down to Miskin and the not always straightforward relationship that those two enjoy. And of course, you now know he’s going to, by the end of the series, take a leap, take a risk, and open himself to potential damage again by beginning a new relationship with Emma Lavenham.

"But it's because of Miskin, it's because of the learning that, I think, has gone there, and because, in a way, he's closed doors before, and that's not completing him. He knows that he has to kind of open it again and take a risk."

Dalgliesh season 3 airs on Thursdays and Fridays on Channel 5.

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