Several major houses are releasing adult coloring books. Some have a spiritual theme and others are like the ones from Penguin Random House, who has acquired the next two coloring books from Johanna Basford, the illustrator behind the bestsellers The Secret Garden and Enchanted Forest books, which kickstarted a bonafide publishing phenomenon. The first book, The Lost Ocean: An Underwater Adventure & Coloring Book, goes on sale October 27, 2015. Read more…