“As I remember, we were working on the paperbacks of When Darkness Loves Us and I reached out to Elizabeth because that’s what you do,” remembers Melissa Singer, then 25 and an editor at Tor. “You make sure you have any corrections, make sure the author’s bio is right, and I naturally asked if she was working on anything else.”

Engstrom did have another book, already completed, but she wasn’t about to let Singer see it. When she’d finished Darkness she was on a high. Darkness had done well, sold overseas, and become a book club selection. She sent Black Ambrosia off to her agent with high hopes, already planning the next stage of her literary career. Then she received a letter from her agent.

“If this is your idea of fiction,” it read. “We are not suited to each other.”

Crushed, Engstrom wrote “Bad Book” on the manuscript box and stuck it on a shelf, picked up the pieces of her broken heart, and moved on to her next book.

When Singer called and asked what she had, Engstrom mentioned the “Bad Book” but said she didn’t want anyone to read it. Singer seduced it off her shelf however, and a few weeks later called and said, “To whom do I make an offer? You or your agent?”

“When I found out she had a novel, that was the first good thing,” Singer says. “But when I found out that it was a vampire novel, that was the second good thing.”

Because vampire books obey different rules than horror novels.

“A lot of people who don’t read horror will read vampires,” Singer says. “They don’t think of vampires as horror. Vampire fiction is a perpetual motion machine.”

Everyone knows the vampire backstory (ancient Greek lamia, John Polidori’s The Vampyre, penny dreadful Varney the Vampire, Bram Stoker’s Dracula, Nosferatu, etc. etc. and so on) but modern vampire revival heated up in the swinging Seventies. In 1975, Fred Saberhagen published The Dracula Tape and in May 1976, Anne Rice published Interview with the Vampire, which just seemed to keep selling. In October 1977 a stage version of Dracula starring studly Frank Langella opened on Broadway with sets and costumes by Edward Gorey, and ran for 925 performances, before closing in 1980. In 1978 Chelsea Quinn Yarbro published the first in her long-running gothic vampire series, Hotel Transylvania (now at around 30 books).

By the time Suzy McKee Charnas’s Vampire Tapestry became a finalist for the Nebulas in 1982, vampire fiction was a big thing, and it only got bigger in 1985 when Rice published her blockbuster sequel to Interview, The Vampire Lestat.

“Vampires are their own subcategory,” Singer says. “And readers have a lot of variety to choose from. Sometimes it’s more pop, sometimes less, sometimes people want stories that play with the tropes—vampires who can walk in daylight—sometimes they want traditional. It’s very a robust genre that never seems to die.”