The hourlong episode visits many of the standard locations of the problems-of-the-inner-city investigation — a high school (where the cameras catch a swirling courtyard brawl), a church, a restaurant started by two former gangbangers. It’s fluidly edited and consistently interesting without turning up any exceptional insights. It closes with a minister who condemns gangster rap lyrics while endorsing Mr. Lamar, followed by a music-video montage.

There are firsthand looks at guns, drugs, piles of money and a “California zipper” — the scar left on a gang member’s abdomen after a bullet wound. But the most engaging sequence is when Mr. Goldbaum visits the grandmother of one of Mr. Lamar’s protégés, who recalls the chaos of the Rodney King riots and rejoices in the knowledge that none of her children have prison records, although most of her grandchildren do. For comic relief, there’s Mr. Goldbaum climbing a fence and looking like Bambi in the crowd at a Lamar concert.

Krishna Andavolu of “Weediquette” is another neatly groomed host on a mission into slightly unusual territory. His first episode is about the use of cannabis oil as a treatment for cancer in children — not just to alleviate the side-effects of chemotherapy but to attack the cancer itself. Among the discussions with researchers and activists, this gives the show the opportunity to show very young children high on weed. (They smile a lot and stare at bugs.)

Mr. Andavolu samples the product, describing the buzz he receives from one-tenth the dose given to children. He repeats his central question in increasingly florid terms — “Is it medicine, or unregulated snake oil?” “Is she living proof that weed works, or a misguided optimist headed for a dark reality?” — and arrives at a solid maybe. It’s a very friendly and very watchable investigation, photographed beautifully in Oregon and California locations.