Every Mary Roach book is crammed full of fascinating characters. In the course of her pop science investigations (Stiff: The Curious Lives of Human Cadavers; Spook: Science Tackles the Afterlife; Bonk: The Curious Coupling of Science and Sex; Packing for Mars: The Curious Science of Life in the Void; and Gulp: Adventures on the Alimentary Canal) Roach often interviews the kind of obsessive minds who used to be referred to as “eccentrics.”

These are people obsessed with one tiny aspect of the human condition, and who also have apparently forgotten how to communicate with ordinary people along the way. They’re odd, and sweet, and sometimes misanthropic people, the kind of weirdos who eat and breathe and (yes, occasionally) defecate one particular subject at the expense of everything else. They are People Who Get Shit Done, the experts in space travel, or entomology, or the use of cadavers in automobile safety who move entire fields forward with their dedication.

But the greatest character in every Mary Roach book is, of course, Mary Roach herself. Roach narrates all her books, and she inserts herself as a character fairly often — she’ll cheerfully volunteer for a sex study, or offer to be used as a target on a paintball range — but you might be surprised if you go back through the books and discover how rarely she refers to herself as “I,” or offers any details about herself that are not directly relevant to the narrative. She’s barely there at all — except, you know, for the fact that she’s in every single word.

This week especially, it feels so important to focus on the people who are dedicated to saving lives, rather than taking them.

Now that she’s on her sixth book — Grunt: The Curious Science of Humans at War — Roach’s character is very well-established. She is, as almost every one of her books suggests in the title, curious. Though Roach has no scientific background to speak of, she immerses herself in every subject until she enjoys the kind of mastery that allows her to pass on complex information through very simple language to her readers. It’s not easy to break a subject as complex as military research down into a series of anecdotes. In every book, you’re watching Roach’s beginner’s brain go from zero to 60 in less than three hundred pages, but her learning process takes place almost entirely behind the scenes.

And the Roach in these books is funny. She never fails to notice a pun, or an irony, or a dry observation. In Grunt, for example, she notes the modern fashion industry’s obsession with camouflage, and how that fed back into the military-industrial complex:

As I write this, you can get on the internet and order camouflage wedding bands, dog sweaters, onesies, condoms, flip-flops, hard hats, and football cleats. Camo print became so popular that eventually Navy personnel began clamoring for it. To the embarrassment of many, the current Navy working uniform is a blue camouflage print. Unsure whether perhaps I was missing the point, I asked a Navy commander about the rationale. He looked down at his trousers and sighed. “That’s so no one can see you if you fall overboard.”

There’s a lot at work in that passage, and it reveals Roach’s final and most important quality: her empathy. It would be easy for Roach to mock the Navy for its sartorial decisions, but she rather gracefully steps aside and lets the commander do it himself, with a gentle self-deprecation. The joke is not on the Navy for being a dumb organization, but on people for being so remarkably people-like in every situation, for choosing impractical form over pragmatic function. Rather than slap together an easy punchline, Roach unveils the raw humanity behind a pair of pants. (Note, too, her excellent use of the word “trousers,” which is about six times as funny as the word “pants” would have been in this context.)

Grunt is interested in the nerdy people who are deeply invested in what at first seems like an apparent oxymoron: they want to make war safer for its combatants. They’re hard at work on fire-retardant cloth, and devising giant guns that fire chickens to test how fighter jets will respond to bird strikes. They’re combating diarrhea and hearing loss. They dissect cadavers to discover how they can help the next generation of soldier cheat death.

Unlike most books about the military, Grunt is not a book that fetishizes guns and other weaponry. “The chicken gun is most of what I have to say about guns,” Roach writes in the beginning of the book. “If you’re wanting to read about the science of military armaments, this is not the book you’re wanting to read.”

Roach is more interested in the search for bomb-proof underwear, and this aspect of the military-industrial complex feels so refreshing that you might never want to read some macho Tom Clancy-style fetishization of artillery again for as long as you may live. This week especially, it feels so important to focus on the people who are dedicated to saving lives, rather than taking them.

Roach’s books are stuffed full of scenes in which she’s being granted a tour by some jaded insider. It’s easy to imagine her as some Columbo type, asking innocuous questions until her tour guide accidentally says something revealing. But sometimes Roach doesn’t even realize that someone is baring his soul to her until later. Here she is, eating dinner with a large table full of Special Operations snipers:

“You know what the hardest thing for us is?” Jack glances around the table. “This right here.”

“Yeah.” I get it. Strangers with their questions and assumptions.

It turns out, Jack wasn’t referring to any of that. By “us” he didn’t mean snipers or Special Operators. He meant the hard of hearing. And “this right here” meant a loud dinner table. Jack says some of his peers cope by asking a lot of questions and pretending to hear the answers. “You see them sitting there nodding, going ‘Uh huh, uh huh.’” Others just withdraw from the interaction.

Let’s leave aside the beautiful symmetry of Roach almost “uh huh, uh huh”-ing her way past an incredibly touching revelation from a man who is probably not very good at sharing intimate details of his interior life for a moment. The wonderful thing about this passage is the way that Roach doesn’t overdramatize Jack’s revelation. She simply shares her mistake, and she gets out of the way and lets Jack speak for himself.

The character that Roach has created in her books provides for marvelous storytelling utility. She can crack a good dick joke on one page and then on the next share the horrific impact of genital mutilation on disabled veterans. She can visit a camp that provides dramatized combat scenarios for training soldiers and make a fictionalized battlefield scene feel as raw as any military fiction you’ve read. Because Roach has so carefully humanized both herself and her subjects, every page feels warm and compassionate.

We’ve all witnessed awkward attempts to bring a human face to science. Many of us have had science teachers who think dad jokes and stunt experiments are a way to introduce a new generation to the joys of the scientific method. Honestly, you could probably produce more STEM students by handing high-school students Roach’s books, advising them that they’re full of fart and sex jokes, and just letting them fall in love with the nerds Roach interviews — the laser-focused geeks who just want to make the world a better place in the only way they can, even if that means watching maggots cannibalize each other in a lab setting for eight hours a day.

In the end, maybe that’s the secret to Roach’s success. The unflagging enthusiasm in her books, the raw happiness that bounces off the pages, isn’t the sort of thing that can be faked. The research and writing that culminates in these pages would not be fun for the vast majority of the population, but Roach seems downright excited to show us what she’s learned every single time. Maybe, when you get down to it, she’s an obsessive nerd for documenting the lives and passions of obsessive nerds.