Two fictional characters are making me crazy. One’s a famous villain, the other, a hero, and lately, they’ve pulled a switcheroo.

Cruella de Vil, the nefarious puppy kidnapper of Dodie Smith’s novel, The Hundred and One Dalmations, is the villain. Ever-popular, her story has been made and remade into film at least four times. And she’s invaded my writing life twice.

In 2014, a magazine reviewer called my antagonist in The Body Business “the Cruella de Vil of the year, the kind of villain you just love to hate.” The description was perfect, though I hadn’t thought about Cruella when I created my own greedy vixen.

That same year, I was asked to name the actor I’d cast as the hero of my book, Samantha Newman, a determined young woman with grit and a fair sense of justice. After Emma Stone’s quirky performance in “Easy A,” I chose her, partly for her physical features, but mostly for her sense of comedy which, like Samantha’s, is tinged with an interesting blend of snark and genuine heart.

Fast forward to today, and imagine my surprise to discover that Emma, my Samantha of choice, is now starring as Cruella in a new Disney release. Presto change-o, hero becomes villain, and I have mental whiplash.