Had you found yourself at the Gertrude Avenue flea market in Richmond, Calif., on Sunday, you’d likely have come across a machine looking like a cross between a glue gun and a ray gun. The device, though, doesn’t have anything to do with Han Solo (sorry) or Martha Stewart (sorry?); it has to do instead with a weapon of a different variety: investigative reporting.

Since last week, California Watch has been offering free lead testing at community centers throughout the state — in Oakland (Thursday), Richmond (Sunday), and Los Angeles (this coming Thursday). The screenings are an extension of a major story the investigative shop and its partner news outlets released earlier this month — a report that uncovered a popular clothing retailer stocking its stores with lead-tainted jewelry, even after it had been cited for the practice by the California attorney general. The piece represents the kind of consumer-defending, outrage-inducing reporting that is the bread and butter of investigative journalism; and yet, at the same time, its core narrative is one that’s hard to tell in a fresh way. “Lead in jewelry is not a new story — it’s been written about, people have heard about it,” California Watch editorial director Mark Katches says of the series. (Indeed, Katches worked on a 2004 Orange County Register series on lead-tainted consumer goods, in this case candy, that was a Pulitzer finalist.) “But if you think the problem has been solved or gone away, you’d be sadly mistaken.”

The trick is highlighting the significance of the ongoing story in ways that will engage readers — and, thus, the hope goes, spur impact. The screenings, which bring California Watch’s lead-tainting story quite literally to life, are meant to do just that. “The stores that have had these problems don’t post any signs, they don’t recall the products, they don’t notify consumers,” Katches told me. “So few of the items we buy in stores are tested or screened in any way.” The lead screenings allow California Watch to step in where stores have been derelict; they create places, Katches says, “where people can come get answers, where we can help them figure things out.”

They also create a way for California Watch reporters to continue their story even after it’s been published and distributed. “We wanted to go the extra step,” Katches says. And that goes for the reporting process, as well: For any piece of jewelry or other item that tests positive, California Watch-ers who are staffing the screenings will record the contact info of the items’ owners for follow-up interviews. As Katches puts it: “It turns into another opportunity for us to do some newsgathering.”

That opportunity doesn’t come cheap: The lead detector in question — officially (and delightfully, in a Popeily kind of way) named the Quickshot XRF — cost California Watch $750 a week, $1,500 overall, to rent out*. But it’s simple to operate — “extremely, Lead Screening for Dummies easy to use,” Katches puts it — and the hope is that the cost will justify itself not only in terms of newsgathering, but also in terms of that other, more slippery goal: engagement. For investigative outfits, in particular, finding ways to invest people in their work — not in a hazy, these-stories-are-good-for-democracy kind of way, but in an urgent, personal way — is a crucial challenge. And one method of tackling it is to re-think what a news story is in the first place. In this case, “the story” is an amalgam that begins with the reporting…and ends not with the news articles and segments themselves, but rather with those articles’ and segments’ life in the real world. Their IRL impact — which is to say, their transformation from “stories” into “events.”

“You talk about engagement; well, this is a great way to engage people,” Katches says. The event California Watch is sponsoring, in this case, is both communal and highly personal. It’s a big-gun approach to audience investment…one that just happens to involve, yes, a big gun.

*This post originally stated $24,000 as the overall rental cost of the gun; that’s the cost to buy the device, though, not to rent it — and a much better deal! Apologies for the error.