One Last Stophits shelvesJune 1, 2021.
ENTERTAINMENT WEEKLY:One Last Stophas been pitched as a queerKate & Leopold.
Was that movie your inspiration or is that just a great marketing peg?

Credit: Valerie Mosley
CASEY MCQUISTON:Its kind of both.
Theres something so romantic about a love that is impossible and that persists anyway.
I dont think I sat down and was like, “Im going to do aKate & Leopoldretelling.”

St. Martin’s Griffin
By the way, watching it in 2020 is hilarious.
There are some plot-relevant reasons that I wont reveal because thats spoilers.
If youve readRed, White & Royal Blue,you know Im a history nerd.
When did you first have the idea for this story?
What if that was true?
The book is set specifically on the Q train.
How did you choose that route?
When I was first researching it, there were a few lines I considered.
Purely for aesthetics, I liked the Q line because Q for queer."
Its really interesting to have a consistent setting in a book that moves.
So I loved the idea that there could be beautiful sunset moments.
It crosses the Manhattan Bridge and the East River, so you get beautiful views from the train.
You recently moved to NYC.
Did that change your outlook or help shape the way you wrote about the city?
When I was first drafting and writing it, I was doing a lot of trips to New York.
[Like] my protagonist, I fell in love with the city and talked myself into moving here.
There were a lot of reasons; it made sense for my career and everything.
But yes, since Ive lived here, theres definitely been details added in copy edits.
Any time I see that my research was correct, its very reassuring.
This cover is so lovely.
It has a similar soft palette and illustrated approach toRed, White & Royal Blue.
How did you end up with this final version?
I really wanted the cover to feel like a moment.
We wanted it to have a very strong sense of place.
We wanted it to feel like New York.
Its about moments in time.
Im a sucker for a sword.