Donald Sobol, the creator of the best-selling Encyclopedia Brown series of mysteries, has passed away at the age of 87. The news of his death was made public this morning; Sobol died last week of natural causes in Miami, according to reports.

Sobol's famous chronicles of 10-year-old Leroy "Encyclopedia" Brown launched nearly 50 years ago with Encyclopedia Brown: Boy Detective in 1963.

Encyclopedia Brown was a proto-hacker, a bad-ass in the style of Buckaroo Banzai and MacGyver, who could sleuth a complicated crime, break it down, and solve it in the span of three pages. In addition to being a whiz kid detective, he was also an entrepreneur who created his own startup detective agency to solve mysteries for the princely sum of "25 cents per day, plus expenses."

Brown was cooler – and nerdier – than Harry Potter, and many of the other heroes of children's books of today. Plus, the Encyclopedia Brown books were designed to be interactive, by the standards of their time – readers could solve the mysteries along with Brown, by reading the text closely and carefully noting down the details of the story.

Sobol's Encyclopedia Brown series was also notable for the inclusion of a strong female lead character. Sally Kimball, Brown's pint-size best friend and sidekick, was also his bodyguard, who protected him from the wiles of local bully Bugs Meany, the leader of a neighborhood gang called the Tigers. Together, Brown and Kimball roamed their fictional town of Idaville, Florida, solving mysteries through an intense reading of the facts.

"In the early 1960s, girls and women weren’t supposed to work up a sweat, and here was a woman doing a man’s work," Sobol told the Oberlin College alumni magazine last year in a rare interview.

For decades, Sobol avoided the spotlight, preferring to live in relative obscurity in Florida with his wife and children. His refusal to do interviews almost approached the hermetic level of J.D. Salinger. He avoided all television interviews, and only rarely granted interviews for articles.

Over the decades, the well-loved children's book series spun out into 28 books, a comic strip and an HBO live-action television series. The books were translated into more than a dozen languages, and sold millions of copies worldwide.

The final Encyclopedia Brown book written by Sobol, Encyclopedia Brown and the Case of the Soccer Scheme, will be published in October.