It’s Nathan for himself, mostly

The comedian leaves nothing to chance in HBO’s introspective, intriguing ‘Rehearsal.’

Nathan Fielder, whose four-season series “Nathan for You” saw him “aiding” struggling small businesses with strange promotional ideas like poo-flavored frozen yogurt or rebranding a Realtor as a “ghost realtor” whose properties are guaranteed to be spook-free, is back.

“The Rehearsal” on HBO takes off from the idea that critical events can be prepared for, that “if you plan for every variable, a happy outcome doesn’t have to be left to chance.” Like the earlier show and the myriad reality shows it half-mimics, it is presented as a sort of social experiment and, in that

Where: HBO

When: 11 p.m. Fridays

Streaming: HBO Max, new episodes weekly

Rated: TV-MA (may be unsuitable for children under age 17)

Allyson Riggs HBO ROLE-PLAY, REPLICAS and carefully engineered situations are at the heart of “The Rehearsal,” a new “reality” series from comedian Nathan Fielder, center.