I've got the whole series on my shelf, so I can walk you through the arc. The first book, 'Murder at the Mayfair Hotel', really is a classic setup. Cleo's down on her luck and has to move into her grandmother's fancy hotel, which immediately puts her at odds with the upper-crust world she's now forced to inhabit. The mystery there is almost a locked-room scenario, introducing her knack for noticing details everyone else misses. It’s a solid foundation, but the character stakes are personal—it’s about proving herself in a new environment.
By the second and third books, you see the world expand. The plots start weaving in recurring characters from the hotel staff and guests, and the crimes begin to touch on broader social issues of the era, like women’s independence and class disparity. Cleo’s confidence grows, and with it, the risks. A through-line about her family’s secrets and a certain elusive antagonist begins to simmer in the background of these middle books, which I appreciated because it gave the standalone mysteries more weight.
The evolution really peaks in the later installments, around books four and five. The mysteries get more complex, often involving multiple suspects and twisted motives that require Cleo to connect dots from past stories. The personal subplot concerning her background comes to a head, forcing her to make choices that affect her place at the hotel and her relationships. The tone shifts slightly, too—there’s more personal danger for her, less of the 'cozy' safety net. The final book I read wrapped up that major family arc in a way that felt earned, though it left the door open for her detective work to continue, which it seems to be doing. The progression isn’t just about harder puzzles; it’s about the hotel setting becoming a character itself, and Cleo’s role within it changing from an outsider to its unofficial protector.