It may not be the kind of hard-boiled Los Angeles crime that attracts the likes of Sam Spade or Jake Gittes, but the police say they have arrested the perpetrators in a series of thefts.

Of Lego.

To be clear, Lego is not a new slang term for cars, diamonds or heroin. The thefts were of literal Lego.

A Target store in San Pedro, Calif., reported some of the thefts, and the police observed Blanca Gudino, 39, of Lawndale, stealing Lego sets at branches of the retailer in Torrance and Lakewood, they said. They followed her to the home of Richard Siegel, 71, in Long Beach, where she delivered the items, they said.

Upon searching the home on Wednesday, the police said they found 2,800 boxes of Lego, with individual values ranging from $20 to “well over” $1,000. They included Star Wars, Harry Potter and Marvel sets, KTLA reported.

The items were being sold to buyers found through online ads, the police said. While the police were on the scene, some prospective buyers showed up at the home.

Ms. Gudino was charged with organized retail theft, a felony, and held on a $20,000 bail. Mr. Siegel was charged with grand theft, also a felony, and was released on his own recognizance.

Mr. Siegel faces a court date on June 26; no court date was immediately posted for Ms. Gudino. Neither could be immediately reached for comment.

Six other thefts of Lego have taken place over the last few months at various Los Angeles-area locations of the chain Bricks & Minifigs, which sells Lego. There was no immediate indication of a link with the Target crimes; the perpetrators were two men, one sometimes serving as a getaway driver.

During one of those thefts, a thief’s headlight shone on a Batman display after hours, casting a shadow of Batman on the wall. Perhaps spooked by the apparent arrival of the Caped Crusader, the thief fled, Katie Leuschner, the store owner, told The Los Angeles Times.

While an organized scam to steal and resell Lego may seem unexpected, perhaps we should not be too surprised.

Lego sets no longer come as bagfuls of pieces that you use to build a rickety house or a car with a wheel missing. Over the years, they have become more elaborate — for example, Lego recently released a kit of the Cathedral of Notre-Dame, comprising 4,383 pieces and, notably, retailing for $229.99.

Lego is pitching these complicated sets more to adults and wants to make Lego a leisure activity, “the same way you would invest time and money in making ceramic bowls,” Genevieve Capa Cruz, the head of product for adults at the Lego Group, told The New York Times recently. Lego sales were up last year, while many other toy companies experienced declines in sales.

Such enthusiasts are called AFOLs, or adult fans of Lego. If you are one, the Lego Tranquil Garden 10315 set comes with 1,363 pieces, if you’re up for that.

Just keep an eye on it.