There’s no denying it: Coloring books for adults are not going away.

Perhaps you already know about the coloring books craze; you might be one of the 1.4 million people who’s bought Johanna Basford’s “Secret Garden.” Published in 2013, it continues to float among Amazon’s best-selling books — currently it’s at No. 10, two spots ahead of Kim Kardashian’s “Selfish” — and is the online retailer’s most-wished-for book. Basford’s follow-up, “Enchanted Forest,” is almost as popular.

The books feature intricate designs that are far too sophisticated for a child’s hand. But for adults, they’re a way to engage creatively with a relatively low barrier of entry: Coloring is easier than most crafts such as, say, learning to knit.

Basford hand-draws and inks all her designs. “My creativity is cultivated by a curious imagination and a delight in the fantastic,” she explained on her website. “Much of my work has roots in the flora and fauna that surrounded me growing up on my parent’s fish farm in rural Scotland.”

Now the artist has signed a contract with Penguin Random House to publish two new books in the U.S. and worldwide. Publishers Weekly reports that the next book, “The Lost Ocean: An Underwater Adventure & Coloring Book,” will reach shelves in October. The book will be, Basford promises, “an enchanting underwater world hidden in the depths of the sea” filled with “exotic fish, curious octopi, and delicately penned seahorses.”