IT'S THE last shot before lunch, and Casanova is wilting. An old scene-hand has just wandered on to the set, singing "You make me mad, you make me sad," and after he's been silenced by a chorus of "Shhhhs", the man who might just be the Scottish acting profession's best-kept secret goes for the umpteenth take.

"I know what men think about," says the great lover, played by Paisley's David Tennant. "All day long, those stupid little inches, driving you mad." Casanova is interrogating his rival, Grimani, over a perceived problem in the breeches department. "Is it big? Is it big enough? Am I any good at all? Is every other man better than me?"

Grimani suggests that Casanova seems to be more in love with men than women, which may or may not be a line added to the lothario's diaries by screenwriter Russell T Davies of Queer As Folk notoriety. Casanova taunts him some more: "Look, if you want a measuring contest, I…

DI Carlisle has it in for Ripley Holden from day one. He takes an instant dislike to the man he's investigating on suspicion of murder… and a shine to the suspect's wife.

David Tennant, who plays the determined detective inspector, refuses to be drawn on his character's principles although he does confess that it's "completely and utterly inappropriate" for him to have an affair with Natalie Holden.

"I won't make moral judgements on the character though, I don't think that's my job, really," laughs the Scotsman, who appeared as the Reverend Gibson in BBC ONE's He Knew He Was Right earlier in the year and has had roles in numerous plays for the Royal Shakespeare Company.

DI Carlisle is drawn in to help out the Blackpool Constabulary when a body is found in Ripley Holden's showpiece arcade. As soon as he meets the hapless entrepreneur, he thinks he's found his man.

But does he believe that Ripley actually committed murder, or i…