A Fly On Your Wall

Danny Dunn, Invisible Boy — Raymond Abrashkin & Jay Williams
Danny Dunn, book 13


Raymond Abrashkin and Jay Williams’ 1974 Danny Dunn, Invisible Boy is a juvenile SF story. It is the thirteenth (and third last) novel in the Danny Dunn series.

Scolded and humiliated when his paper airplane bounces off his English teacher mid-class, Danny Dunn wonders if his life would be better if he could be invisible at will. He discusses the matter with his chums Irene and Joe. Joe, who has been reading mysteries, suggests that misdirection is the best way to attain practical invisibility. Danny would prefer true invisibility, but is willing to give misdirection a try. The trio tries to use misdirection to steal cookies under the nose of Danny’s mom; they fail abjectly.

But Mrs. Dunn’s scientist employer, Professor Bullfinch, uses the distraction provided by the trio’s attempt to actually steal some cookies. Crumbs on the professor’s shirt give the game away.

This gives Danny to think. It reminds Danny that his mom’s boss is a brilliant if impractical genius. If anyone could figure out true invisibility, surely it would be Bullfinch


What Bullfinch does have is a material that is one fortuitous accident away (accidents caused by Danny) from being turned into a cutting-edge semiconductor. Bullfinch then uses the new semiconductor in a device he calls an ISIT (Invisibility Simulator with Intromittent Transmission). It’s a remotely piloted mechanical dragonfly. It allows the person flying the little dragonfly a good look at anything the device can see. The dragonfly is small enough that it is easy to overlook.

It doesn’t take the trio and their mentor long to fly the device straight into an ethical quandary. They surveil series antagonist Eddie “Snitcher” Phillips and spot him stealing the answers to an upcoming spelling bee.

They would love to turn the tables on the Snitcher, but snitching on classmates to a teacher is also wrong. They come up with a cunning plan: they will use the speaker on the ISIT to alarm Snitcher into betraying himself.

Useful thing, that ISIT.

Which is why General Gruntl and his soldiers descend en masse on the professor’s household. Having heard about ISIT from a mutual acquaintance, Gruntl is interested in the device’s potential for spying and miscellaneous skullduggery. It could be used to keep an eye on subversives. Or an eye on the Other Side (dastardly foreign enemy). It must be firmly clutched in government hands, lest the Other Side steal the device and use it to spy on America. Horrors!

When Bullfinch refuses to give up the device, Gruntl stations a guard around the professor’s house. No idealist academic is going to stop Gruntl from protecting America from enemies foreign and domestic, enemies real and enemies entirely imagined. Which leaves the job of freeing the household to Danny, Irene, and Joe.

Pity that the guards have orders to shoot to kill.


Danny was very talented at accidentally creating marvellous materials. This was a plot point in the first book in the series, Danny Dunn and the Antigravity Paint1. Presumably the professor has kept the widow Dunn as his housekeeper in large part thanks to her son, who can be counted upon to cause serendipitous lab accidents. Well, it may also have something to do with the fact that the absent-minded professor doesn’t seem to know how to operate a broom, mop, or stove.

It’s been decades since I read these books so some details escape me. I sorta kinda remember that a new wondrous material is created in most or all of the books. I don’t remember what happens these materials at the end of the book. They must somehow be used up or abandoned, because if they had made their way out into the wider world, that world would have been utterly changed and the books would no longer have had a familiar setting.

Something I mercifully forgot (and cringed to encounter again) was the treatment accorded poor Irene. She is as science-minded as Danny, and quite enterprising and bright. But she’s the only girl on the baseball team and singled out for verbal abuse. How dare a girl play sports!

At last, Danny said to Irene, “I’ve been thinking about what Snitcher said. Does it bother you much to be the only girl on the team?”

Some,” Irene admitted. “I get the feeling that everybody is looking twice as hard at me as at anyone else. They expect me to do worse than everybody else — or maybe better. Either way, it makes me nervous.”

But at least Joe and Danny have her back.

Don’t let it get you down.” Joe tipped his head back to admire his neat lettering. “You know, it’s funny,” he said. “There’ll be both boys and girls in the spelling bee, and nobody thinks anything about it. There’ll be boys and girls with exhibits in the science show — if there were only boys, people would think it was peculiar. So why should they think it’s so strange if there are boys and girls playing baseball together?”

It’s because girls aren’t supposed to be good at games,” said Irene.

No, that’s not it, because girls do play all the games boys do and everybody knows it.”

Well, boys are supposed to be better at them.”

Whoever made up that rule didn’t know about me,” Joe protested. “The only game I’m any good at is checkers.”

Or what about George Bessel?” said Danny. “He runs about as fast as an inch-worm, and can’t throw a ball any farther than across the street. The only reason he’s on Snitcher’s team is that they’re friends.”

In 1974, when this book was published, acceptance of women’s equality was not the usual attitude.

The kids were canny in their use of what we now call social engineering. If they were to raid the lab to free the ISIT, they might be shot. Instead they use the soldiers’ expectations about kids to sidestep the armed guards. They do this so effectively that the soldiers never connect kids doing kid-stuff with the sudden absence of the ISIT.

The book is written in easy-to-read prose, as is to be expected, given that it was aimed at middle school kids. Still, there was more to the book than I expected. It was like re-watching a Rocky and Bullwinkle episode as an adult and realizing that when you’d watched it as a kid, you’d missed a lot of the jokes and references.

Danny Dunn, Invisible Boy is out of print.

1: The Danny Dunn books came out over the course of twenty-one years, but Danny Dunn never grew up. It’s as if all Danny’s adventures were compressed within a couple of years. Once a month Bullfinch invented something that would up-end society if widely adopted … and it wasn’t.


  • Chuk

    These books were great. He also did a good one shot about a kid in the modern day whose grandpa was a wizard.

  • Mike D

    Amazon reports 13 Danny Dunn books on Kindle


  • Mike D

    ISFDB has 15 in the series



    Danny Dunn ◦1 Danny Dunn and the Anti-Gravity Paint (1956) by Raymond Abrashkin and Jay Williams ◦2 Danny Dunn on a Desert Island (1957) by Raymond Abrashkin and Jay Williams ◦3 Danny Dunn and the Homework Machine (1958) by Raymond Abrashkin and Jay Williams also appeared as: ◾ Variant: The Homework Machine (1960)

    ◦4 Danny Dunn and the Weather Machine (1959) by Raymond Abrashkin and Jay Williams ◦5 Danny Dunn on the Ocean Floor (1960) by Raymond Abrashkin and Jay Williams ◦6 Danny Dunn and the Fossil Cave (1961) by Raymond Abrashkin and Jay Williams ◦7 Danny Dunn and the Heat Ray (1962) by Raymond Abrashkin and Jay Williams ◦8 Danny Dunn, Time Traveler (1963) by Raymond Abrashkin and Jay Williams also appeared as: ◾ Variant: Danny Dunn—Time Traveller (1965)

    ◦9 Danny Dunn and the Automatic House (1965) by Raymond Abrashkin and Jay Williams ◦10 Danny Dunn and the Voice from Space (1967) by Raymond Abrashkin and Jay Williams ◦11 Danny Dunn and the Smallifying Machine (1969) by Raymond Abrashkin and Jay Williams ◦12 Danny Dunn and the Swamp Monster (1971) by Raymond Abrashkin and Jay Williams ◦13 Danny Dunn, Invisible Boy (1974) by Raymond Abrashkin and Jay Williams ◦14 Danny Dunn, Scientific Detective (1975) by Raymond Abrashkin and Jay Williams ◦15 Danny Dunn and the Universal Glue (1977) by Raymond Abrashkin and Jay Williams

  • Rachel Sommer

    I loved these, especially because I identified with Irene. I found them by looking for books with the atomic symbol on the binding in the Spuyten Duyvil branch of the New York Public Library.

  • Beth

    I liked these as a kid; it's good to know that they'd probably still be fun to read now.

    I can't believe you skipped a chance to use the word "antepenultimate." This was the antepenultimate Danny Dunn book.

  • Evan

    I loved these books as a kid, and re-read them when I was grown, and this was the only one that I thought held up. None of the others ever explored the potential downsides of the gee-whiz inventions the way this one did, and the idea that the government couldn't always be trusted to do the right thing was a new one to me when I was in fourth grade.

  • Chakat Firepaw

    "Once a month Bullfinch invented something that would up-end society if widely adopted … and it wasn’t."

    Compressing the timeline like that does offer something of a solution: The world is going to see a wave of society changing technologies come out, it's just that the books end before that happens. Similar to why Forest Tales hasn't seen any further uses of the transformation effect that changed the human Dale Perkins into the chakat Goldendale¹. Chakat Oceanwalker is still doing the massive amount of R&D required to turn the result of a desperate attempt to save a life into a controllable procedure.

    1: Well, besides the lack of output in general. That's because ponies.

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