Considering the current fashion of making everything into a procedural, and one with a male and female lead to boot, and with Restoration England recently in my mind, I've decided there's an obvious tv show opportunity here in the Interregnunm, those eleven years (1649 - 1660) between Charles. I. execution and Charles II. return to England, when England was a republic.

Now, the male detective would be young Charles II. Who had ample time at his hands during his exile, was eternally short of cash and on the move on continental Europe between Holland (where his sister Mary of Orange lived), France (where his mother, being a sister of the late Louis XIII, found shelter with his youngest sister, Henriette Anne aka Minette) and various principalities that would have him for a while. Charles was undoubtedly the smartest of the Stuarts and never short of a bonmot, which is good for a detective, and he really needed money. (For a while, his mother when he was dining with her in the Louvre made him pay for his part of the food.) He also was physically fit and good at escaping dire situations. (See famous escape out of England after the battle of Worcester disguised as a peasant.)

The female lead? A member of a Dutch merchant company who had provided Charles with some cash and then realised there was really not much of a chance to ever see it again, or even getting royal favours out of it. (Remember, no one at the time knew whether this Republic thing would be permanent or not, whether or not it would survive Cromwell, and thus whether or not Charles would ever be in a position to do anything for anyone.) Our heroine's original job is making sure the merchant company gets at least SOMETHING for its money, which is, solving crimes that have a negative impact on the company's trade otherwise. If he has nothing else, Charles has access to Royal circles at the continent where our bourgois heroine would not get to, so there's that.

Big twist before the mid season hiatus: we find out the Dutch merchant company isn't our heroine's only employer: she also works for OLIVER CROMWELL as his secret agent abroad, supposedly to keep an eye on Charles (at least in theory, if he ever got enough cash by, say, marriage to a rich princess, he could try an invasion). She's also half English and her parents have suffered awful fates in the reign of Charles I., which was part of the reason why she works for Cromwell.

Considering the audience knows Charles will make it to the English throne alive post Interregnum, the main suspense has to be in the fictional female lead's fate and decisions. And since there's entire decade to choose from, the show is good for 5 to 7 seasons. The episodes set in France can also be stealthy Musketeers crossovers, given the most recent version was cancelled (free actors) and this era is roughly the one (immediately after) Dumas' first Musketeers sequel, "20 Years Later".