Muscle-popping energy radiates from Ross MacDonald's children's debut, Another Perfect Day. In this sun-drenched picture book, which mimes the heroic style of 1930s ads and comics, a squared-jawed uebermensch named Jack enjoys a "perfect day" of wrestling alligators, defeating alien invaders and taste-testing ice cream. "Aaaaaah! Life is rich!" Jack proclaims. Readers discover that Jack is the alter-ego of a dreaming boy, who wakes up to begin his own perfect day.

MacDonald needed Jack's superhuman stamina in his early years, when he began his illustration career in his native Canada. He had moderate success in selling his linocuts and woodcuts to magazines, but he also painted houses to make ends meet. In 1985, he became a full-time illustrator; two years later he moved from Toronto to New York City. Today, he works out of his own printing studio, Brightworks Press, behind his home in Newtown, Conn.

MacDonald exorcises his residual angst in his depiction of broad-shouldered Jack, whose tailored blue suit (in the boy's dream) is replaced by a fluttery pink skirt. "In New York I'd be schlumping around to my studio, all these Wall Street types shoving me out of the way," MacDonald says with a laugh. "I finally got my revenge. It's irresistible to have them appear in a tutu against their will."

As his career took off, MacDonald seldom thought about writing for children. He considered his over-the-top humor inappropriate for minors; as evidence, he cites his recent parody of Viagra ads ("Your Penis Is Shrinking"). His friend, literary agent Holly McGhee, encouraged him to create a picture book anyway. "I was really flattered, but I told her, 'I just don't see it,' " he says. "My style was back-page illustration, wise-ass. I thought it was the polar opposite of anything you'd want to do for kids."

In the interest of "mollifying Holly," he says, "I wrote a proposal about a boy who runs away and joins the circus." One publisher bit, but the project lost its appeal for MacDonald. "I had to illustrate a one-page spot every two weeks [for PC magazine], and sometimes I got so bored," he says. "I thought, if I do a kids' book I've got to love it, because it's gonna go on much longer than two weeks."

Only then did MacDonald produce the manuscript for Another Perfect Day. "I wrote it over the course of two days, maybe a total of five hours' work," he says, with mild amazement. "I used lined paper, with word balloons. Everything fell together."

Consequently, he had the book dummy in his studio when designer Hans Teensma brought a friend, Neal Porter, to tour Brightworks Press and order some stationery. "We're talking about the letterhead, and Neal says, 'I've been working at Dorling Kindersley, and I left to go on my own as a freelance children's publisher,' " MacDonald recalls. "I got out the manuscript. I think he visibly flinched. But when I read it for him he flipped and said, 'I'm gonna publish this book!' " Porter thought Another Perfect Day would be a good addition to the list of Roaring Brook Press, the new trade imprint of Millbrook Press in Brookfield, Conn., which Porter had recently joined.

"I said I would talk to my agent," MacDonald says, "and since I hadn't really signed with Holly, I thought I'd better sign with her quick."

Before committing to Roaring Brook, MacDonald and McGhee shopped the manuscript to other publishers. Responses were positive but unsatisfying to MacDonald. "Everybody wanted to change the dang thing," he says.

He bristled at editors' suggestions that Another Perfect Day's Gatsby-esque guy should be the dreaming boy's father or wear a superhero costume. "The thing is, Jack is the little boy's idea of what an adult male is really like," MacDonald grouses. He decided Porter, who believed in the book, should be his editor: "I'm not the least bit superstitious, but I love the serendipity of the whole thing," he says.

From the start, MacDonald gave the characters and settings a retro-1930s appearance, with a nod to the 19th-century chromolithography and typesetting techniques he admires. "It's more or less my usual magazine style," he says. "I like Thomas Nast and George Cruikshank, but I can't draw people in bustles and bonnets, so I mix an 1850s style with an early 20th-century look."

He prepared the final art using his own idiosyncratic method. "I do my sketches very small, literally one or two inches high," he explains. "I boil them down to action and expression, then blow them up on the Xerox." He traces the enlarged photocopies in a terracotta pencil-crayon, soaks the paper and paints the image "wet-on-wet, so there's no going back," he says. "After the thing is dry, I go over the line again in indigo blue, so it sparkles."

When it came time to print Another Perfect Day, MacDonald says he had one request: that the book be printed on ivory-colored paper with an eggshell finish. "To me, printing is part of the creative process," he says, and he is very particular about production. His next book, Atchoo! Bang! Crash! The Noisy Alphabet¸ also for Roaring Brook, takes advantage of his extensive collection of 19th-century wooded fonts, and a sequel to Another Perfect Day is in the works.

Nevertheless, MacDonald's first loyalty is to magazine illustration. "[Advertising and book cover artist] Brad Holland is quoted as saying, 'I'm not an illustrator,' " he says. "I think that's a weird attitude. In illustration, you get incredible social commentary--it's such a rich field, stuff that's produced for the public. I'm proud to say I'm an illustrator."