There is an eerie quality to Spermworld. Lance Oppenheim’s documentary is about an unregulated online universe: men who offer their sperm directly to parents so that everyone avoids the expensive fees of sperm banks and fertility clinics. Oppenheim’s idea came after reading “The Sperm Kings Have a Problem: Too Much Demand,” a 2021 New York Times article written by Nellie Bowles. Oppenheim and Bowles connected and then collaborated on research. Several donors and recipients are interviewed in the documentary, but the focus is on three donors in particular: Nagel (who has fathered more than 130 children), Stefan, and Tyree. Oppenheim filmed first meetings in empty parking lots and motel rooms, moments between donors and their already-born children, and intimate interviews. Though helping parents in need, these donors reveal motives that include sexual reasons, charity to women, and the thrill of fathering many babies. “I think that kind of existential question is the thing that animates each scene,” says Oppenheim. —Jeanne Malle