The Moonspinners/Nine Coaches Waiting/The Ivy Tree/Madam, Will You Talk? - Mary Stewart
Buddy Read of Madam, Will You Talk with Diane Lynn & Hj 3.5

All the elements of a good Mary Stewart novel are here:
A strong female lead in Charity Selborne
A child in danger in David Shelley
A man who may or may not be a villain and murderer in Richard Shelley
Throw in some Insta-love and stir well!

We also get a potential wicked step-mother, (and I could tell from the very first pages something was off about her. Then when it was revealed she'd lied about Richard dying to David I realized what a monster she was.) and lots of assorted baddies who keep you guessing as to who they really are and where they fit into this mystery.

I think all the car chases and having Charity be such a superb driver was quite a twist for the time period--1955--the book was written.

My only complaint and squick factor was when Richard actually hurt Charity badly enough to leave bruises on her wrist that she later had to cover up with a bracelet. She still had them at the end of the book when he proposed to her and I don't think it's addressed again except for a comment where it mentions Richard's "rueful grin" which is not a proper apology. Whether he thought she was involved or not, he shouldn't have hurt her. I took off 1/2 a point for this.

Not my favorite so far of all I've read but interesting to see earlier examples of insta-love after having read so many current YA full of this trope.