Guess the Plot
Captive of the Sea
2. In 15th-century London, a fair maiden falls for a sailor just before he leaves on a years-long voyage. Unable to find a suitable husband, she waits for her crush to return. But will he still want her when he discovers she's working in a house of ill repute?
3. Captured and placed in the Cleveland Aquarium, Nemo finds himself in the same tank with the barracuda that ate his mom. He escapes into the aquarium castle, only to end up behind bars in the castle's dungeon. Can Bruce the shark rescue him?
4. When feisty aqua-humanoid Namor wins a trip to the Moon, will his essentially pseudo-amphibian physiology hold him back from realising his dreams? Join the plucky fish-man in his quest to become the next Neil Armstrong and discover how easily laser-powered jet packs can incinerate your thighs.
5. Mara is stranded on a desert island. Her only way off is to marry the merprince and live forever 20,000 leagues below the waves. She's fine with long walks on the sand at sunset. By herself. And the occasional airdrop from the mythopoetic society.
6. A marine biology degree was supposed to help Patsy Greene save the whales. Instead it leads to life-and-death survival with killer hurricanes, cutthroat pirates, and watery tea. At least she can fill out a few more of the never-ending grant applications while waiting to meet Davy Jones. Also, ornery dolphins.
Original Version
Mawdlen [Cunnick] was born on King Arthur's grave.
That is the story her father told her, [Was Mawdlen's mother onboard with giving birth on King Arthur's grave?] along with legends of the King and his daring knights, who fell afoul of lovely maidens and fought their way through perils back into grace and favour. Then the battles of the kings of her own time begin anew, and Master Cunnick packs up his household and brings them to the teeming, reeking city of London. After some years, though the Wars of the Roses continue, [Presumably you don't refer to them as the Wars of the Roses, as they weren't called this till more than a century after they ended, or so I'm told.] their own hardships ease as Master Cunnick finds a measure of success as a merchant. One day, delivering her father's noon meal at his warehouse, Mawdlen meets a young sailor named [Mawkesh.] Santiago. He wins her heart, because he too speaks of knights and of errantry, but he is not yet master of his own ship, and when his captain sails, he must leave, too. [Or he could stay and become a knight, much more impressive to Mawdlen than just speaking of knights.]
The years pass and Mawdlen is now over late to be married, but she fancies none of her suitors, no matter how many fetes and dances she attends at the home of wealthier friends. Wealthier, because Master Cunnick's fortune has failed him, and every day the family's luck and prosperity dwindle further and her father sinks into dissolution. Mawdlen finds an opportunity to help and, unbeknownst to her family, begins to deliver goods for a back street merchant, not a member of any guild. She is unaware of the other businesses operating from the establishment. [Perhaps she should have looked at the sign on the front of the building.]
CAPTIVE OF THE SEA is a historical complete at 58,600 words.
Notes
While Mawdlen was admittedly a known name in the 1500's, using it may lead readers to think you gave her that name because "maudlin," which means self-pitying or sentimental, often through drunkenness, is an apt description of her.
This is a bit long for a query summary, and the first two paragraphs are spent setting up the situation. They could be reduced to:
As Mawdlen Cunnick awaits the return of her beau/true love Santiago from a lengthy sea voyage, she aids her increasingly destitute family by taking a job delivering goods for a London merchant. A merchant who, unbeknownst to Mawdlen, has his hands in numerous corrupt and illegal businesses, from a prostitution ring to a gang of thieves.
Now there's plenty of room to get to your plot, which I assume is how Mawdlen's family becomes entangled in the villain's clutches and how M & S can escape those clutches. What's their plan, what are the obstacles, what will happen if they fail?