From episode 1: "He's dressed in basic black slacks, neatly pressed, and a dress shirt of a royal blue. Around his waist is a belt fitted with many oddly shaped compartments, and an unpolished platinum sheath for a very short sword. His red necktie is monogrammed 'HG' in yellow. A long blue cape with a faint shimmer to it flutters behind him. Topping off the ensemble, a light helmet consisting of a skullcap and a mask that comes down over his eyes. The helmet sports a yellow feather, which he insists makes him look 'jaunty'."
Hair: brown, cut short
Eyes: brownish green, or, if you will, greenish brown
Height: 6' 1.5" (187 cm)
Weight: 190 lbs (86 kg)

Hydrogen Guy can mentally control the physical, chemical and nuclear state of the element hydrogen; can control the physical and chemical structure of compounds that contain a "significant" amount of hydrogen. "Super-atomic" senses of taste and smell allow him to identify the chemical composition of materials, and he can pinpoint trace elements up to a few parts per billion. He has a robust immunity to most conventional poisons. Briefly he can assume certain properties of hydrogen at standard temperature and pressure: he can achieve short bursts of super-speed due to the hydrogen atom's high mobility; low density of hydrogen gas allows him to float (but not fly); he can briefly transform himself into a cloud of hydrogen gas, at a high energy cost. Powers, particularly reflexes, are enhanced when using the Ruler of Elendil.

The Ruler of Elendil, a mystical 40 cm (16 in) wooden ruler created by Blaise Pascal and wielded in secret by many great warrior-physicists of the past. It glows with a blue light in the presence of evil. The Ruler appears to be made of light varnished pine, with thin brass blade along the measuring edge. The structure is magically enhanced - the blade can slice through any substance found outside of a neutron star, and any force capable of shattering the Ruler would also tear through spacetime itself. Hydrogen Guy has developed a sort of empathic link to the Ruler from long use. The possible sentience or degree thereof of the Ruler is a subject best left to idle coffeehouse musings.

Hot chocolate, light on the argon, with maybe a trace amount of rare earths for extra spice. (It's the f-orbitals that give it the kick.) Now that he's tottering into his late twenties, though, he's drinking more tea than he used to.

Hydrogen Guy's view of reality is rotated 45 degrees with respect to most everyone else's, which has been an advantage in both of his chosen careers. He is a brilliant deductive reasoner in the tradition of Sherlock Holmes, although Holmes never had cases like Hydrogen Guy's. His actions sometimes appear reckless, although they always seem the best idea to him at the time.

For some time, Hydrogen Guy had mixed feelings about this whole superhero business - it was all very exciting and interesting, sure, and one met all kinds of interesting people, but it did seriously cut into his time for theorising and loafing in cafés. Not to mention all that other stuff about having a normal life, which Evans always found a challenge anyway. But others had alternate plans for him, and now since having his destiny revealed to him and later, joining the UN Justice Council, he's giving it his all. His partners may possibly miss those more dissonant days.

It was revealed to him by N - a sort of near-omnipotent being called a "Mage" - that his Elemental powers are genetic relics of a vanished galactic empire, the Ancient Republic. Hydrogen Elementals served as leaders of a warrior caste of super-powered defenders. Hydrogen Guy is the first of the new order of Elemental to emerge. However, he is less than thrilled with this link to an ancient and questionable past.

Hydrogen Guy generally gets on well with his fellow heroes. Deuterium Boy tends to swing between admiration and exasperation with his partner. Helium Girl doesn't seem to take a great deal of notice of him. Chuck War tends to regard him as a sort of baffling younger brother. Other members of the League of Heroes regard him as their Fearless Leader. The Navy Blue Sparrow took to him immediately, and became his stand-in sidekick on several adventures around Ontario and Québec. There are exceptions, naturally - Americana loathes him, and while Captain Toronto respects him, he sees Hydrogen Guy as frequently misguided (especially with respect to his own wisdom and experience).

As Jim Evans, he works at the Maple Ridge Institute for High Energy Physics. His work has received some acclaim - although none of us can say exactly what this work involves, other than it's very mathematical and somehow involved with modelling the periodic table - and several years ago he shared Torrado's Zerfelda Prize in Physics with David Marcolin. In 2000, he spent a rather eventful four months as a guest worker at the National Research Council in Ottawa, while keeping an eye on the Crustacean.

Evans was engaged prior to his trip to Torrado, but this ended when his fiancée decided to trade places with her look-alike, the Princess. Ah, youth. He's had little time for things like dating since - frankly, he tends to avoid the whole mess - but he's recently started seeing one Katrina "Kate" Nereid on a regular basis. Things seem to be going well there. Kate is an actuary whom Evans asked out spontaneously at the Usual Coffee Shop. They went on one date, which was something of a disaster due to lobster-related shenanigans. Their second date was more than a year later, after Evans gained a bit of perspective after going to Hell and back and repelling an alien invasion. Carpe diem, don't you know. Kate doesn't know that her beau is actually the notorious Bohr Warrior, and he suspects she wouldn't approve. To complicate matters further, Kate's close friend is Lola Lakefront-Property, the reporter that Hydrogen Guy loves to annoy and with whom he has a bit of unresolved romantic tension. Well, on his side of the equation, anyway.