But actually doing the work is hard, and in the amniotic infinity pool of celebrity that BoJack floats in, there are too many incentives just to do the easy thing. BoJack is, among other things, an addict — booze, drugs, sex — and the endorphin rush of public adulation is one of the toughest buzzes for him to kick.

The Oscar campaign provides the arc of the new season, as BoJack endures press interviews (including one with a reporter from “Manatee Fair”) and schmoozes with industry types at parties including a “bat bat mitzvah,” where the young celebrant becoming an adult is, in fact, a bat. (“BoJack” is not above a broad animal joke; when Ana orders soup in a restaurant, the waiter who brings it is, naturally, a fly.)

The absurdist comedy and hallucinatory visuals match the series’s take on Hollywood as a reality-distortion field. But the series never takes an attitude of easy superiority to its showbiz characters. At heart, “BoJack Horseman” is a comedy about lonely people (and animals) who are never by themselves.

That melancholy spirit comes through beautifully in the stunning fourth episode of the new season, in which BoJack has to attend the premiere of “Secretariat” at the Pacific Ocean Film Fest, held underwater.

When he arrives by submarine, he’s fitted with a diving helmet that muffles the sound, and the sea creatures speak in unintelligible squeaks. He can’t understand anyone, and no one can understand him. Cranky and confused, BoJack wanders off and ends up on an underwater bus, helping a pregnant male sea horse (biology lesson here) deliver a litter of babies.