Keeley Hawes on her latest BBC TV series Summer of Rockets

Keeley Hawes stars in Summer of Rockets alongside Toby Stephens. Picture: Sophie Mutevelian

Over the last few years, she’s become one of our biggest TV stars, sealed by her incredible turn in Bodyguard.

Other shows in the last 12 months include Mrs Wilson, Traitors and a return to The Durrells – and now she can be seen in new BBC2 drama Summer Of Rockets, penned by Stephen Poliakoff.

It was the first time Hawes, 43, had collaborated with the writer/director, famous for BBC dramas such as Shooting The Past, Dancing On The Edge and Close To The Enemy.

“My husband’s worked with him, so I’d heard first-hand about what it’s like to work with him,” says the London-born actress, who’s married to Matthew Macfayden (they met on the set of Spooks).

“And I’ve met him over the years quite a few times and I was getting a bit annoyed about that because he hadn’t cast me!” she quips.

“But yeah, he works unlike anybody else, so the whole thing is a very different discipline.”

The series is set in the UK during the tumultuous year of 1958. At the centre of the story is Russian Jewish emigre Samuel (played by Toby Stephens), a designer of bespoke hearing aids, who is asked to demonstrate his work by MI5.

But that’s not really what they want from him. He is actually tasked with secretly obtaining information about some new friends of his – Kathleen, played by Hawes, and her MP husband Richard (Linus Roache).

In a period of history that was full of uncertainty about the future, the show asks, who can you really trust?

As for why Kathleen was an interesting character to play, Hawes calls her “very much a woman of her time”.

“She lives for her husband in this perfect home and her perfect life and wonderful son in this beautiful countryside,” continues the star.

“There’s nothing wrong with wanting to be the perfect wife and mother, of course there isn’t, but this is a woman who doesn’t have any ambition to do anything else, which is very alien to me.

“So it’s interesting to play that, and quite suffocating, but ultimately that’s how she feels.”

Another intriguing plot development is that Kathleen and Richard have a secret – their 21-year-old son has gone missing.

“They don’t go to the press about it because it would look very bad for the family,” says Hawes, who has three children of her own – two with Macfayden and one from her first marriage to Spencer McCallum.

“So it’s this awful secret and they don’t know if the police have looked into it, but he’s literally disappeared. And this is a time without the internet and social media, when it was easier to disappear than now.

“He disappears a couple of days after his 21st birthday and they have no clue why. It becomes her life’s work to find out where he is and why he’s left. And she doesn’t have a job so she can just dedicate everything to that.”

Although it’s an emotional storyline to play out, Hawes says because of the time period, Kathleen’s feelings are “all stifled”.

Hawes has starred in many different period dramas – arguably one of her most memorable roles was BBC’s Upstairs Downstairs which aired from 2010 to 2012. Asked about the appeal of this genre, she says simply: “They’re diverse. This year I’ve gone from Thirties, Forties, Fifties, into the Sixties on a few jobs and it’s quite odd that I just think it comes in waves and there seems to be a fashion.”

What made the filming experience of Summer Of Rockets stand out though was the rehearsal time they had with Poliakoff, along with his writing methods.

“The scripts never change,” notes Hawes. “That’s incredibly rare. I don’t think a word of it has changed.

“Jed Mercurio [writer of Bodyguard] was talking about writing and he said he probably wouldn’t be a writer without laptops.

“Stephen has always hand written everything and he still hand writes everything, which is really amazing. And then he dictates it to an assistant and so nothing ever changes because he’s handwritten it and there’s nothing he hasn’t covered.”

Then there’s her look in Summer Of Rockets; stunning red-head wig, bright lipstick and fancy dresses. Considering previous roles like Line Of Duty have seen her be anything but, does she like getting the chance to look glamorous?

“Oh, I couldn’t give a s**t about it,” she says, laughing again. “I couldn’t care less. I really couldn’t.

“I always find it fascinating what people can do to you – you walk into a make-up truck and walk out looking like a totally different person.”

Summer Of Rockets starts on BBC2 on Wednesday 22 May at 9pm.