Here's how it commenced: One night when I was 12, maybe 13, I caught the film Ten Little Indians on TV. It was the 1965 version - not the best (see 1945's And Then There Were None), but compelling all the same.
The setup and execution (literally!) really grabbed me: Take 10 strangers, strand them in an isolated mansion, and toss in some shadowy past sins, a slew of quirky murders, and an embedded killer, and what have you got? The beginning of an Agatha Christie reader.
Not long after that evening, I learned that the person who'd dreamed up that dastardly little soirée was a rather renowned Englishwoman, well-born and cultured, who'd been responsible for scores of cold-blooded murders.
That week I invested in my first Christie novel. It was a Dell paperback called Murder After Hours (a.k.a. The Hollow).