The self-confident yet clueless young detective Stephan Pastis, introduced in Timmy Failure: Mistakes Were Made, will return in a second misadventure, Timmy Failure: Now Look What You’ve Done, whose title and cover are revealed here for the first time. Candlewick will release the illustrated middle-grade novel in February 2014.

Young readers clearly took a shining to this bumbling hero, who runs the Total Failure detective agency with a 1,500-pound polar bear named Total. The first book, released by Candlewick in February, sold more than 130,000 copies in the U.S. alone during its first two months on sale, and immediately moved onto the New York Times bestseller list and the national Indie bestseller list. Rights to the novel have been sold into 28 countries.

Mistakes Were Made was the debut children’s book from Pastis, the creator of Pearls Before Swine, a syndicated comic strip that appears in more than 600 U.S. newspapers. Pastis is gratified by the positive response to the novel from readers across a broad age range. “It was such a thrill and remains a thrill,” he says of readers’ reactions. “The biggest surprise for me is to hear adults say they love the book. And the response from kids has been truly amazing.”

Before trying his hand at children’s fiction, the author received some good advice from Wimpy Kid creator Jeff Kinney. “He visited my studio and said, ‘Just be funny,’ ” recalls Pastis. “That sounds simple, but it’s so easy to get caught up on plot. But I took what Jeff said to heart. In my parlance, I try to make each chapter its own comic strip, with an opening, a funny ending, and jokes in the middle. Kids have so many distractions that I know I have to work to keep their attention. I guess I have an advantage, having done my comic strip for 12 years. When you’re in the newspapers every day, you get immediate feedback, and you get a sense of what works and what doesn’t.”

Pastis is finishing up revisions on Now Look What You’ve Done, in which Timmy sets out to win a schoolwide competition to determine who stole a globe from the superintendent’s office. “Timmy’s insulted that they’d even have a contest, since he knows he’s not only the best detective in the school, but in the whole world,” says Pastis. “Of course he starts out on the wrong foot and does an absolutely miserable job with the case.”

The author, who’s hoping to write a third Timmy Failure novel (“I’m starting to collect notes for it and the pile is getting bigger and bigger, so that’s always a good sign”), is happy to be attending BEA for the first time as a children’s book author. “It’s an exciting scene, and I’m looking forward to seeing booksellers I’ve met over the years while touring for my Pearls Before Swine collections,” he says.

Old and new fans can meet Pastis today when he signs copies of Timmy Failure: Mistakes Were Made at the Candlewick booth (C1575), 10–11:30 a.m.