There are a lot of ideas in this world that start off bad and never get any better—so many, in fact, that it comes off as miraculous when an idea that, at first blush, seems terrible turns out on execution to actually be pretty good.

Whatever happened to that Smoking Man from the X-Files?

Which is a roundabout way of saying that the artistic triumph and cultural influence of Pee-wee’s Playhouse, the TV show that ran on Saturday mornings from 1986 to 1991—and the genesis, production and impact of which are documented in Caseen Gaines’ Inside Pee-wee’s Playhouse—utterly blindsided me at the time.

I was never quite the right age for the Pee-wee Herman experience, I suppose. The hosted kiddy show was in its waning days during my childhood. We still had Captain Kangaroo, and the brief 1970s revival of Howdy Doody, and local mainstays like Boston’s beloved TV cowboy Rex Trailer; but even then it was clear that this sort of thing was a throwback, and not long for this world in a mediascape beginning to fill up with Japanese battle robots and Masters of the Universe.

I did admire The Pee-wee Herman Show, the stage production-turned-HBO special that introduced the character. But if Pee-wee was to have legs, I would have said his future lay in feature films like Pee-wee’s Big Adventure. To do an actual children’s show based around the character seemed as pointless and as perverse as trying to bring back vaudeville.

Shows what I know. What Paul Reubens wagered on—what I failed to factor—is that the very thing that seems played-out to the young adult is spanking-new to the small child. And in truth, Pee-wee’s Playhouse really was something new. There had never been anything quite like it; it was simultaneously knowingly old-fashioned and consciously cutting-edge, visually assaultive, aurally abrasive (encouraging the kids at home to scream whenever the heard the “secret word”) but possessed of a genuine whimsy and largeness of spirit. The message of Pee-wee’s Playhouse is that it’s OK to be yourself—your marvelous, oddball self—and that true friends accept and celebrate each other’s eccentricities.

In this, as in all things, the show took its cues from its star. Reubens controlled virtually every aspect of the show, co-directing most of the series’ run and personally approving all scripting and art direction. And in his Pee-wee persona, he was capable of great generosity to young fans. In a small but telling anecdote, he uses his approval power over the show’s merchandising to veto any proposed toys that would need batteries, on the grounds that such a requirement would make them less usable for low-income children.

But that single-mindedness had its dark side. When Phil Hartman, who had worked with Reubens on the original Pee-wee Herman Show, left the Playhouse for Saturday Night Live, Reubens took it as a personal betrayal, and the two were never reconciled. And when the Pee-wee Herman Show was revived for the stage in 2010, voice actors George McGrath and Alison Mork, who had been a part of the Playhouse crew throughout its run, were cut from the show at the last minute, replaced by cheaper non-union actors.

Gaines, though a self-proclaimed Pee-wee superfan, does not shy away or soft-pedal the less savory aspects of Reubens’ history, but the picture he paints is of an essentially well-intentioned figure—driven, plagued with that odd sort of tunnel vision that afflicts highly creative people, occasionally tone-deaf, occasionally reckless, but with his heart in the right place. For all its attraction for the superfan, from the exhaustive episode guide to the previously unpublished photographs and behind-the-scenes  tech-talk, the human portrait of Paul Reubens stands as Gaines’ signal achievement.

Jack Feerick is a critic-at-large for Popdose.