Sequelitis has so infected Hollywood that even a mediocre comedy like 2011’s “Horrible Bosses” has spawned a follow-up that, true to form, is even worse than its predecessor. The first film was at least mildly amusing in spots. This one—more frantic and stupid, and considerably more vulgar—offers a few throwaway lines that might cause you to crack a smile, an occasional good reaction shot from Jason Bateman, and an energetic turn from Chris Pine, but otherwise it’s more tedious than funny. The title adjective might be a little too harsh as a description, but not by much.

The set-up has the three wacky pals from the first movie—goofy Dale (Charlie Day) and lascivious Kurt (Jason Sudeikis), whose antics are an endless source of exasperation to more sensible Nick (Bateman)—inventing a device called the Shower Buddy, which they plan to manufacture and market and—they hope—make a fortune from. The opening portrays them trying to promote the thing on a live Los Angeles TV morning show, a bit that provides a foretaste of the tone to follow by being crude in terms of both sexual innuendo and jocular racism while allowing for lots of frenzied comic bickering between the guys.

Amazingly, the disastrous spot—perhaps designed as a homage to the old Vitameatavegamin routine from “I Love Lucy”—catches the eye of a couple of major retail investment types, sleazy Bert Hanson (Christoph Waltz) and his playboy son Rex (Pine), who contract to buy 100,000 units if the guys will take out a start-up loan to produce them. Of course once the things are ready, the Hansons renege on the deal, intending to let the new business go bankrupt and buy the inventory at pennies on the dollar while the naïve trio go bust.

That induces our supposed heroes to hatch a plot to kidnap Rex and force Bert to pay a big ransom for his return. That requires them once again to seek advice from their old criminal pal Dean “Motherfucker”” Jones (Jamie Foxx), as well as from Nick’s nasty one-time boss Dave Harken (Kevin Spacey), who’s now in prison. And pulling it off involves breaking into the office of Dale’s former boss, nymphomaniac dentist Julia Harris (Jennifer Aniston), to steal the gas that they’ll use to put Rex under. All the hands from the first movie—except, of course, for Colin Farrell’s Bobby, who was killed in it—are thus on hand again. (Farrell should thank his lucky stars.) Of course things to not go as planned. Rex turns the tables on the boobs, insisting that they go through with their scheme but hand over most of the loot to him. The script by director Sean Anders and John Morris thus becomes not just another rip-off of “Nine to Five” (as the first movie was), but of “Ruthless People,” too—or its ultimate inspiration, “The Ransom of Red Chief”—although Bert does get the cops involved, in the person of a dour lieutenant (Jonathan Banks, looking more bulldog than ever).

The borrowing wouldn’t be fatal if the outcome justified it, but like its predecessor “Horrible Bosses 2” doesn’t live up to its models. The routines played out by Bateman, Sudeikis and Day get tiresome very quickly, with Day’s constant screaming, in particular, grating rather than funny. (Gene Wilder did this sort of nervous-Nellie stuff much better. So did Don Knotts, in fact.) The bits offered by Spacey, Foxx and Aniston come off like cadenzas fit awkwardly into the plot to shoehorn them all back into the mix. Pine adds some spark to things by going for broke, but Waltz seems totally at sea, playing his part relatively straight. Even in the blooper reel that forms part of the final credits, he doesn’t seem amused by a car door that refuses to open for him; the others laugh uproariously over their own silliness, obviously having a lot more fun than anybody in the audience will.

On the technical side, the picture is barely adequate, looking for all the world like B-level studio fodder. But if you’re going to cut corners on a script, you’re probably not going to worry too much about such niceties as cinematography (Julio Macat) or production design (Clayton Hartley). They shouldn’t be blamed overmuch, though; it would be hard for anyone to be inspired to his best efforts by material like this, especially since Anders seems content to allow his stars—and cameo players—improvise at will, and at inordinate length.

Come to think of it, perhaps “horrible” isn’t too far off the mark, after all.