In terms of telly, the Second World War is, without doubt, the best one. The uniforms of the opposing armies are sufficiently different to alleviate confusion during battlefield scenes, the Americans pile in half-way - which facilitates the casting of exciting Hollywood stars - and in the end, the British, who are without doubt the goodies, win! Huzzah!

Consider, by contrast, the English Civil War. It's a difficult war to love. Who are we supposed to be rooting for? The Roundheads are fighting for democracy - a set of attributes that almost infallibly signal “the goodies”. But when Cromwell eventually attains power, he bans Christmas - in effect, murders Santa - which puts him in a pop-culture category with the Grinch and the White Witch.

And what are you supposed to make of the Cavaliers? They might be running the country into the ground - what with their fascistic views on religion and democracy, punitive taxes, etc. But then, they have great hair. Whenever you see a group of humungo-wigged Cavalier soldiers marching off to war, curls bouncing in the sun, you feel like singing “Here come the girls” and doing the stirring-up-a-pot-of-funk dance. Again, great hair almost infallibly signals a goodie. Our Pavlovian instinct is to root for the glossy locks of the Cavalier. It's all so confusing.

Of course, the final, and greatest problem of the English Civil War, is: who wins? The English win - hurrah! But the English also lose - boo! And that's the big Civil War problem. Thousands of people die, the character of a nation is called into doubt - and it doesn't give you a straightforward storyline. Oh, the humanity.

Considerable props, then, to Peter Flannery - the screenwriting demi-god behind Our Friends in the North - who has chopped the Civil War up into four quality chunks for The Devil's Whore. Flannery engages our attention by making the centre of his story neither Roundheads, nor Cavaliers, but Angelica Fanshawe. Married to a Cavalier, instinctively Roundhead, Angelica eventually knocks all the Roundhead/Cavalier nonsense on the head, to become an independent lady highwaymanlady. I know. Amazing.

Angelica is played by Andrea Riseborough - who is so hot in this that she might well get a Bafta for keeping the elderly warm this winter. Having previously managed the impossible - making Margaret Thatcher saucy in Thatcher: The Long Walk To Finchley - Riseborough has an all-out field-day playing a fruity 17th-century noblewoman who has to fight her way out of a revolution, in a corset. Riseborough is totally, army-haltingly beautiful in this: her face is a bowl of cherries and doves. Her eyes are like a family-sized sex-feast, for four. With a free litre of Coke. Even surrounded by wars, castles and kings, she is the centre of every frame.

Her alarming gorgeousness is amplified by the director Marc Munden, who lights the whole thing like a Rembrandt - rich, cross-hatched gloom, with occasional splashes of face, lace or red velvet. Taking full advantage of the gloom is John Simm as Edward Sexby, a 17th-century mercenary who existed in real life. Simm plays Sexby as a saturnine, primal item. With his receding, manky hair and gigantic facial scar, Sam Tyler from Life On Mars has turned into Lieutenant Worf from Star Trek. He doesn't speak much. All he wants to do is fight, and then retreat into a corner to sniff Riseborough's blue silk garters, stolen at sword-point. To be fair, it's a perfectly reasonable desire. Rounding off the list of bonanza performances is Peter Capaldi as Charles I, who appears to be moved around on wheels by courtiers, allowing him to enter and leave scenes with an oily, supernatural silence.

By and large, there are two categories of period drama. The first is White Petticoat Drama, where people do a bit of frisky fan-work, have a picnic that involves a huge ham, and then live happily ever after. The second is Dirty Period Drama - where everyone is covered in boils, wees out of the window, and palpably suffers from the lack of antibiotics and/or mobile telecommunications. The Devil's Whore is definitely in the second category. John Simm's fleas should make the credit list. Oliver Cromwell clearly pongs. It makes a dirty war a very dirty war. But one that, against all the Civil War odds, makes great telly.

The Devil's Whore, C4, Wed, 9pm

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