It’s always an irresistible treat to peek inside the private notebooks and sketchbooks of some of the world’s greatest artists, typographers, naturalists, architects, and designers. But it’s especially delightful to peek inside the private world of one of modern history’s most celebrated creative minds. That’s precisely what archivist Karen Falk offers in Imagination Illustrated: The Jim Henson Journal (public library) — a revealing glimpse into the life and artistic process of the beloved Muppets creator through a selection of rare sketches, storyboards, photographs, personal notes, doodles, production drawings, and other never-before-published ephemera.

Lisa Henson, Jim’s daughter, writes in the foreword:

Everyone knows that Jim Henson created the Muppets, and that he performed the most famous Muppet of all, Kermit the Frog. … What no one really understands is how much other creative stuff was going on in my father’s mind. Jim spent almost all of his waking hours in some form of creative activity, which was as natural for him as smiling and walking are for other people. What he produced was only a fraction of all the ideas that he had, and what we generally see today is only a fraction of what he produced.

[…]

Because creativity is a process, it is also rewarding to focus on it more than the finished projects. In this book, you are able to see snapshots of my father’s creative process, flashes of his inspirations, and his memories of the milestones that were the highlights of his personal and professional life.

Though Henson was no match for history’s famous diarists, he used his sketchbook as a kind of “memory warehouse” where he noted both the events of his life and the riotous activity of his imagination. Falk writes in the introduction:

Jim often used blank books to sketch out ideas for specific projects or designs for characters, and once or twice, tried to start a diary containing longer accounts of events and his related feelings, but always set them aside after a short period. This journal is the only continuous effort of this sort, covering almost his entire adult life.

Falk writes of Henson’s experimental films in the mid-1960s:

Along with the Muppets, Jim had a parallel outlet for his creative energies. Having acquired a Bolex 16mm camera and animation equipment, Jim eagerly pursued other methods of expressing himself. He painted under the camera, filmed cut paper as it danced to jazz riffs and syncopated rhythms, and shot abstract footage of lights, trees and city streets. This led to the existential live-action shorts, including Time Piece in 1964, which was nominated for an Oscar, and hour-long documentary or dramatic pieces that aired on Experiments in Television. Tempted to focus on his live-action filmmaking career and pursue grown-up projects like a psychedelic nightclub, the decade ended with a tug back to puppets. Jim was invited t participate in the development of a revolutionary children’s show, Sesame Street, which premiered in November 1969.

Meticulously annotated and lovingly compiled, Imagination Illustrated: The Jim Henson Journal is at once an invaluable record of modern creative history and an affectionate celebration of Henson’s legacy and magic.