David Walliams plays Greville White
David Walliams, currently one of the biggest stars on British television due to the success of BBC One sketch-show, Little Britain, is delighted to play Greville White in Poliakoff's absorbing psychological drama.
Greville is the charismatic, yet sinister, social chameleon who tries to draw an up-and-coming columnist called Mary Gilbert into his inner circle. When she rebuffs his advances, he makes it his mission to destroy her.
David, 36, reveals that he was desperate to play this fascinating character, but had to work hard to get the part: "It was a very thorough process," recalls the actor, who has also appeared in Hotel Babylon, Attachments, Waking The Dead, Marple and A Cock And Bull Story.
"I had two two-hour auditions which really gave me the chance to give a half-decent performance. Stephen and I were also able to discuss the part in depth. The writing is so rich, you have to work very hard as an actor.
"You can't use tricks or throw lines away. Every line is there for a very good reason, so you have to deliver a really detailed performance. What is great is that because he both writes and directs, Stephen has a very clear vision. You know you can put yourself in his hands and trust him absolutely."
The versatile performer, who last year raised over £1million for Sport Relief by completing a cross-Channel swim in the astonishingly fast time of ten-and-a-half hours, felt this was a role which he could really get his teeth into.
"Greville is a fascinating character. He's a socialite who hangs about with toffs in country houses. He seems like a parasite because you don't know what he does for a living.
"However, Greville reveals his truly dark side when he encounters Mary at an elite social gathering. She is a threat to him because she's full of these fresh ideas.
"When he realises that he can't control her, he has to destroy her. It's a metaphor for how the established order in the Fifties would put down people who had innovative ideas."
David adds: "Of course, you can't play it as a metaphor. You have to play it as a love story even though the couple never actually touch. I see it as a love story because the way Greville thinks he can control Mary is by seducing her. That's in the title Capturing Mary.
"He wants to own her sexually, and then make sure that she doesn't upset the established order. But when she won't be corralled, he ruins her. You don't actually see him doing it, but when the older Mary talks about how editors won't return her calls, you get the sense that he used his network of allies to destroy her."
So does David know anyone like Greville?
"Oh yes, he's a familiar figure," the actor replies with a smile. "At parties in London, you often meet people who claim to run art galleries or write for newspapers, but you're not quite sure what they do. Most of all they claim to know everyone who's everyone. They could be dangerous because their trade is information and gossip and that has great currency."
It is this rare sense of depth and complexity that distinguishes Stephen's films. "TV drama is not normally like this, it's normally very literal," the actor comments.
"But Stephen's work is more like a play, it has subtext and intellectual rigour. He's our greatest TV dramatist. He's chosen to work in television because he has more control than he would have in the movies.
"No-one can tell him what to do about casting, and no-one can tamper with his script. He has proven time after time that he can do it, so commissioning editors really trust his vision. And they're absolutely right to do so.
"What I love most about Stephen's work is that you never know what's going to happen next. He doesn't have familiar tropes and he's not in the least bit formulaic and that really marks him out. Even with Dennis Potter, you always had expectations that there would be songs or sex or dream sequences. With Stephen, nothing is ever predictable."
When this film shot David had just finished a worldwide tour of Little Britain. He laughs: "I was meant to take a holiday but this offer was too good to turn down. Great work lasts a lifetime. Stephen's Caught On A Train, for instance, still stands up. This is a once in a lifetime opportunity."