After pickpocketing the zookeeper’s keys as he bids goodnight to the animals, a gorilla surreptitiously unlocks cage after cage and the menagerie follows the unsuspecting man home. Simple yet sly, the art-driven plot of Peggy Rathmann’s Good Night, Gorilla has been entertaining children at bedtime for nearly two decades, and Putnam is marking the book’s upcoming 20th anniversary with a new hardcover edition. Rathmann adds an author’s note to the commemorative edition, which features a 9 x 11” trim size – 30 percent larger than the original 1994 volume – and also contains some newly tweaked art. The first 17,000 copies sold will include a print of the book’s cover art, signed by the author.

Continuously in print in hardcover, Good Night, Gorilla also has a robust sales history in board book format. Putnam released a standard-size board book in 1996, and an oversize board book appeared in 2004, as did Buenos Noches, Gorila, a standard-size Spanish board book. Of the three million copies of all Putnam Good Night, Gorilla editions in print, more than 2.5 million are board books.

Rathmann’s original inspiration for the book sprang from a childhood memory. “When I was little, the highlight of the summer was running barefoot through the grass, in the dark, screaming,” she recalled. “We played kick-the-can, and three-times-around-the-house, and sometimes we just stood staring into other people’s windows, wondering what it would be like to go home to someone else’s house.”

Rathmann first wrote the story as an assignment for a children’s book writing and illustration class at the Otis Parsons School of Design in Los Angeles. She noted that the first half of the book “popped right out,” but she spent two years on the second half.

“The original story was only 19 pages long,” she explained. “It ended with the zookeeper and his wife being shocked to find a gorilla in their bed. So we concocted a variety of alternate endings. In the process, my editor, Arthur Levine, invented the ‘eyeballs page’ and my art director, Nanette Stevenson, wisely suggested that the zookeeper’s wife take a leadership role. I don’t remember who thought up the twist at the end possibly the guy at my local copy shop.”

How ‘Gorilla’ Found a Home

Levine, now v-p and publisher of Arthur A. Levine Books at Scholastic, was an executive editor at Putnam when he first encountered Rathmann’s work. He had acquired Bootsie Barker Bites, a picture book by Barbara Bottner, who was Rathmann’s teacher at Otis. “Barbara gave me the manuscript, along with some illustrations by one of her students,” he said. “I immediately said, ‘Holy goodness’ – these are wonderful!’ and signed up Peggy to illustrate the book.”

The editor then acquired two solo works by Rathmann, Good Night, Gorilla and Officer Buckle and Gloria, for which she won the 1996 Caldecott Medal. Levine, who called Good Night, Gorilla “one of my favorite books from my whole career,” said its success derives from Rathmann’s “ability to combine warmth and humor, and ability to tell both plots and subplots in a text of incredibly few words.” As Levine put it, “There is nothing gimmicky about the book. It comes purely out of Peggy’s storyteller’s impulse. The book still works remarkably well.”

Margaret Frith, who was president of the Putnam & Grosset Group when Levine acquired Rathmann’s debut solo books, also remembered being immediately drawn to the author’s work. “One morning, Arthur came into my office wearing a big smile,” she said. “He was holding dummies of Good Night, Gorilla and Officer Buckle and Gloria. I took one look and, like Arthur, knew that here was a remarkable talent. That Good Night, Gorilla is turning 20 comes as no surprise. I have found that the books children love forever are, most often, those created by authors and artists who remember their childhoods vividly. A Peggy memory always brings laughter to the lucky listener.”

In response to comments from readers over the years, Rathmann revisited some of her original illustrations for Good Night, Gorilla for the 20th anniversary edition. In the initial hardcover, a pink balloon appears in almost every picture. “Readers wrote to say that there should have been a pink balloon in every picture, so I added the missing balloons,” she said.

Another issue that troubled young fans of the book was the fact that all the animals have a toy in their cages – except for one. “A number of distraught parents wrote to confess they had been forced to fabricate the whereabouts of the lion’s toy in order to get their children to go to sleep,” said Rathmann. “One mother asked me if it’s okay if she says the lion is sitting on his toy, and I felt for her. So, for the new edition, we pulled a stuffed animal out from under the lion.”

Did the author find the task of signing 17,000 prints for the anniversary edition daunting? “It was actually pretty fun,” she replied. “My husband is a project manager and loves doing impossible jobs. He passed me the prints and I signed them while we listened to Barbara Kingsolver read Flight Behavior on tape. I signed 17,000 posters in 12 days. I think we might have set a speed record.”

That Good Night, Gorilla has been lulling children to sleep for 20 years, Rathmann said, “is gratifying beyond words. The other day, a lovely bookstore owner told me that her grandson, who has cerebral palsy, would wiggle and giggle when they turned to the ‘eyeballs page,’ and that his very first words were, ‘Good night, good night, good night.’ It made my year. Heck, it made my life.”

Good Night, Gorilla: 20th Anniversary Edition by Peggy Rathmann. Putnam, $16.99 Oct. ISBN 978-0-399-22445-4