Once upon a time, in a Europe not so different from our own, there was a tiny Balkan country called Syldavia. When uranium was accidentally discovered in the Zmyhlpathian Mountains, the normally peaceful Syldavians embarked upon an ambitious nuclear energy program, protected by a sinister counter-espionage organization known only by the acronym ZEPO. Work began on a top-secret nuclear powered rocket, capable of sending a heavy payload out of the earth's atmosphere. On a still summer evening, the Syldavians surprised the world by launching the X-FLR6 on a mysterious course for outer space...

The story sounds less and less like a CNN news brief once it's revealed that the rocket is actually bound for the moon, manned by a doddering old scientist, an alcoholic sailor, a teenage reporter named Tintin and his cockerspaniel, Snowy. No need to stop the presses--it's only the premise for Destination Moon (1959), a Sputnik-era comic book by the Belgian illustrator Herge. Tintin and his two human companions, Captain Haddock and Professor Calculus, eventually touch the surface of the moon, romp about in orange space suits and endure who-knows-how-many plots to steal the spacecraft. While the plot summary may sound like standard comic book fare, the genius is in the details. In his evocation of crackpot Balkan generals, shady military organizations and political doublespeak, Herge created a fictional world that eerily resembles our own--at least from a distance.

Tintin's 21 illustrated adventures, which have been translated into over 28 different languages (including Icelandic, Catalan and Welsh), hold some claim to the title of "Greatest Children's Books Ever Written." As a child, I gobbled up these slim, multi-colored volumes like chocolate. I don't remember how I first came across them. Perhaps my parents bought one for me on a lark, or I saw them in a school library or at a friend's house. In any case, they were the perfect companion for a child who spent large chunks of his days poring over maps and atlases, reading about ancient civilizations and foreign intrigue.

More so than anything else I read at a young age, Tintin kindled my fascination with writing, foreign affairs and travel. The eponymous hero of Herge's series is a young newspaper journalist who travels about the world solving one scandalous affair after another (and manages to spend surprisingly zero time at the office). Opium smuggling in the Orient, counterfeiting schemes in Scotland and underwater treasuring hunting pose no problem for the resourceful Tintin. With the aid of Captain Haddock and pet dog Snowy, Tintin makes short work of the thugs and brings the ringleaders to justice.

On the surface, Tintin's moral universe is fairly simple. There's little moral ambiguity: The good guys are good, the bad are guys bad, although sometimes the good guys also turn out to be bad guys. No one acts out of mixed motives, and no evil deed goes unpunished for too long.

But when I return to these children's books with an adult eye, this world becomes a stranger and much more melancholic place. For all his glamor and gumption, Tintin is an emotionally inscrutable character. Like another eternally young character, Peter Pan, Tintin's refusal to grow up (or settle down) betrays an ineffable sadness that clings to his beige trenchcoat.

No sooner does Tintin solve one mystery than he is plunged headlong into the next--a mysterious stranger collapses at his doorstep, a treasure map is discovered, or Professor Calculus is kidnapped (once again) by shady foreign spies. Caught in a world of constant motion, there's hardly a moment for him to catch his breath before setting off again on some new adventure. The last panel of a Tintin book rarely depicts anything other than a scene of departure: we bid farewell to the boy reporter as he steams away on an ocean liner, boards an airplane or blasts off into the night sky in his rocket ship. An old man and his courageous son, recently rescued from the clutches of some nefarious revolutionary cell, stand on the dock and wave their handkerchiefs.

What keeps Tintin moving at this relentless pace? The young reader takes it for granted that Tintin will always be on the move, just as he assumes that the Hardy Boys will always be on the trail of one more mystery. But for the grownup reader, it's difficult not to interpret Tintin's constant motion as an evasion of mortality. Tintin's metabolism, like that of all other children's book characters, is governed by a simple law: Stop moving and you grow old and die. Archie and Jughead keep driving around suburbia for the very reason that once they stop, settle down and get married, they become subject to the same laws as the rest of us--baldness, fatness and disillusion. The youthful complexion of the comic book character, who never seems to age a single year in all his adventures, is attributable solely to his shark-like motion through the printed world.

Hence Tintin's mysterious age. He's evidently not a grownup, but not quite a boy either. All the tell-tale signs of puberty, such as facial hair and acne, are strangely absent. His skin is as baby-smooth in "The Blue Lotus" (set in 1930s Shanghai) as it is in his final adventure, "Tintin and The Picaros" (set in 1970s Latin America). Forty years without a single zit or wrinkle! That's as amazing an ability as Superman's X-ray vision.

Tintin's fundamental ambiguity extends all the way to his sexual orientation. He never appears to have any close female friends (with the revealing exception of Madame Castafiore, a campy opera diva whose path he crosses several times). And to complicate matters further, he's constantly having quasi homoerotic relationships with young boys whom he befriends in foreign countries. Tintin's physical appearance is itself gender-ambiguous. What are we to make of his distinctive cow lick, which is neither particularly masculine or feminine?

These are mysteries that, in the end, we must live with if we are to fully appreciate Tintin for who he is. Perhaps the enduring appeal of Tintin lies not only in the richness of his adventures, but in his psyche as well. Behind every hidden plan or smuggler's lair lurks a deeper secret, the secret of the self and its composition. Tintin holds the lantern out to us, and so we follow...

Joshua Derman is a senior living in Quincy House. This is what happens if you concentrate in philosophy.