There was a long, long tradition of Greek and doctoring, so there was a lot of information that have been passed down by this time. They didn't have a lot of the drugs that we have now, but they had a fairly good understanding of the human body. SIMON: The - what was the state of medicine? You have an after-note in the book where you talked about - that it can still impress you how much they got right and it can appall you how much was absolute nonsense. Although some of them achieve fame and fortune, quite a lot of them were not popular and not respected, and rightly so.

People were quite scathing about doctors. DOWNIE: He would not be tremendously well respected. What would a doctor in the ancient Roman Empire - what would that experience to be a portal for him to see? DOWNIE: It was - when we went on a trip to Hadrian's Wall and we saw a caption in the museum that said Roman soldiers were not allowed to marry but they were allowed to have relationships with local women, and I thought that there's got to be a story there. SIMON: So what of ancient Britannia, Roman Britannia called to you to set the story here?

SIMON: Now this is your first novel, right? And when I was younger, oh, I used to catch this bus into school and the bus would go past the Roman Walls of Colchester - so it's all around us, really. Most of them have been knocked down and dug up since, but there's a lot here that you can just walk around and look at. There are a lot of Roman remains in Britain. Tell us how you learned all the fine details about the Roman Empire and let me warn you in advance if you say, oh, it's all on the Internet, I'm going to be very disappointed. RUTH DOWNIE (Author, 'Medicus: A Novel of the Roman Empire'): Oh, thanks for inviting me, Scott. Downie, thanks very much for being with us. Ruth Downie joins us from the studios of the BBC in Northampton, England.

Ruth Downie's new book, her first novel, is called 'Medicus.' It's an English murder mystery set in the ancient Roman Empire and inflected with British wit. And in a moment of unexpected generosity Ruso is moved to buy a pathetic slave girl, Tilla, who has a broken arm and he finds himself investigating the deaths of prostitutes who had worked out of a local tavern. The provincial outpost is Britannia, which is now Chester, England. Worst of all, the food stinks, literally. He's an officer, an army doctor of the Roman Empire who feels cast adrift in a place teeming with squalid beggars, importuning pimps, currish dogs, unbathed slaves with matted hair and locals with thick, funny accents. Gaius Petrius Ruso was a man of education and elegance doing his duty in a savage land.

Ruth downie medicus series in order