
Congratulations on retirement. Since you loved Agatha Christie and want clever twists without the scares, I think Thursday Murder Club is a perfect fit. It follows a group of sharp retirees in a British village who tackle a proper whodunit, complete with fair clues, red herrings, and a warm, witty tone that stays miles away from gore.
It scratches the puzzle itch in that classic way and it is the first of a four book series, so you have a comfortable run ahead. The focus stays on solving the mystery through clue spotting and character insight rather than thrills, which makes it cozy and satisfying to unwind with.