It has been received as a tour de force, perhaps even a career-defining performance, but Maggie Gyllenhaal had to be convinced to take on the role of Nessa Stein, the contained, fractured lead of BBC2 spy thriller The Honourable Woman.

"I felt she was alarmed by me, the project, and the whole idea," the show's writer and director, Hugo Blick, said on Friday.

It is little wonder: the remarkable eight-part series, which follows Stein as she attempts to build reconciliation between Israel and Palestine against a backdrop of international secret service conspiracies and at great personal cost, is a demanding watch. And Blick asks a great deal of his lead, whose character is kidnapped, beaten and raped twice. In the penultimate episode, which aired on Thursday, she was the target of a bombing and the show ended with her missing, presumed dead.

"Maggie has a poise, she has a coolness to her, she has an intellectual rigour, and it's the carapace of cool intellect that surrounds this schismed personality that makes the character fascinating," Blick said. "That's why Nessa speaks in these modulated tones when we first meet her. Maggie had that tension from the get-go."

There was also the issue of persuading a film actor to move to the small screen. "She's an Oscar nominee. It's a big deal for her to say, OK, I'll come across to this new ground. I think she still had a bridge to cross in her attitude towards film and towards television. But she's more than happily crossed it since making this piece."

The Honourable Woman, which has been attracting around 2.5 million viewers, could be cited as a perfect example of what many regard as a golden age of television, which is currently outshining film. It is both a political drama and a spy thriller, cinematic in its ambition, and it tells a complex story from many perspectives, covering a particularly divisive conflict, over the course of eight hours.

Some viewers found its languid stride too slow, particularly in the first three episodes, which lingered over details, and moved at the same unhurried pace as Stein's speech patterns.

"I disagree with them," Blick said. "The first three episodes are a portrait of a woman in shock, and then we understand why that is in episode four. So that glacial nature of her character is to do with her still coming to terms with [the rape] eight years ago. It's not to do with me wanting to feel beautiful about each shot. It's to say, look, this person is outside of our normal senses. She's detached. I thought that was really important."

Blick said the harrowing first rape scene, which occurred, in flashback, when Stein was in captivity, was not a light choice. "Too often, when issues of rape become the kernel of a female character … Within dramas, within the context of a thriller, rape is used as a storytelling device so glibly. We make it the middle of our story."

The second ("controlled consensual sex which goes wrong") was an extension of the fallout from the first, Blick suggested. "It's important that the character was trying to orbit the problem by returning to it, or returning to the danger of it, and going across that line. Not because of her, of course. Rape is still rape, no matter how it occurs."

Both scenes were extremely difficult to watch, but neither felt unnecessary.

In its gender balance, The Honourable Woman is an unusual proposition. The spy thriller is a traditionally masculine arena and Blick's previous series, the acclaimed and highly stylised noir The Shadow Line (also for BBC2), was, "quite 'testosterone' because of the nature of the genre", he said. Here, though, almost all the key characters are women, from MI6 boss Julia Walsh (Janet McTeer) to the mysterious housekeeper/translator Atika (Lubna Azabal) and the shadowy spy Monica Chatwin (Eve Best).

"I was really excited – consciously at the start, though I forgot it very quickly – to place women in the story as characters who are not archetypes," Blick said.

It is amusing that the one character accused of getting ahead through strategic sex is a man – Stephen Rea's droll spy Hugh Hayden-Hoyle – while in the final episode, McTeer delivers a zinger of a line about getting the job done as a woman, which it would be cruel to spoil now.

Though it was three years in the making, the first episode aired at almost the same time as the resurgence of violence in Jerusalem, and as a drama set against the backdrop of Israeli-Palestinian conflict, it could not be more timely.

"When I researched it I was in Hebron, 18 months ago, and in the region nobody is in any doubt that it's a complication that has never gone away," Blick said. "It's like a volcano that goes down and comes back up. I knew it was going to come back. I didn't realise it was going to come back now."

Blick said he had some concerns about how it might be received, and whether viewers might think he was attempting to capitalise on the conflict. "But there's a dexterity to the storytelling that comes from perspectives on either side of that divide, as the story progresses, and I've been really pleased to see the audiences and the critical faculties engaging with that. I hope that it is a rigorous look at the motivations of characters on either side."

That's not to say that Blick felt pressured to offer balance, in the traditional sense. In fact, in the final episode, something of a line is drawn, though it is buried under the opaque moral uncertainty of no side behaving well.

"I didn't want to state one thing, then undermine it by balancing it from the other side. That becomes an enervating experience, and people give up because you're not taking a viewpoint or perspective. You have some instances that are very pro-Israeli in the early stages of the story, then you're looking at, for instance, corruption in the educational system in Israeli society, that is a form of racism. One is true, and so is the other, so how do we feel about that? I thought it was exciting."

According to sources, the US first lady, Michelle Obama, has requested a copy of the series. "I hear it's a rumour!" Blick laughed. "I'll tell you what, if Michelle Obama was kind enough to watch this show all the way through, then that would be a very positive thing indeed, because of the argument that it presents. Yes, it's a thriller, but I think it does attempt to address some acute psychological angles within the conflict as it exists. It says a couple of things which are politically important. It would be great if that was heard."