It’s been a summer to forget for Hollywood — unless, of course, you are a comic-book movie star.

Heading into the next-to-last weekend of the summer movie season, the US box office was running 13.4 percent below last summer, according to comScore.

And little help is on the way through the Labor Day weekend.

In fact, the summer appears to be limping toward the close. Last weekend’s $96 million gross was the year’s lowest, BoxOfficeMojo reported.

This penultimate weekend may be even worse — perhaps the lighest August weekend in 20 years.

“It may be that rare weekend where no movie opens to more than $10 million,” said Paul Dergarabedian, comScore’s senior media analyst. “In this context, the [Mayweather-McGregor] fight is just insult to injury.”

With only $3.6 billion in summer box-office receipts, Dergarabedian is already on record that this will be Hollywood’s first sub-$4 billion summer since 2006.

“It’s going to end with a whimper,” he said.

As with any disaster, there is plenty of blame to go around for the poor Hollywood summer.

Franchise fatigue invariably gets called out first for causing such a dismal season.

Disney’s “Pirates of the Caribbean: Dead Men Tell No Tales” and Paramount’s “Transformers: The Last Knight” both did well overseas.

Domestically, however, the $172 million gross for “Pirates 5” is the first time the series has scored less than $200 million.

“Transformers 5” has only brought in $130 million — compared to $245 million for its previous incarnation in 2014 — despite opening in June with little competition.

“The Mummy” was also a reboot, although the fourth iteration suffered not only from over-familiarity, but also from bad reviews.

Even “Mummy 3, with Brendan Fraser in the lead nine years ago, did 22 percent better than the $80 million generated by Tom Cruise’s star turn.

R-rated comedies also flopped this summer, with the spectacular exception of “Girls Trip.”

“It worked — it was just the right antidote to summer blockbusters,” Dergarabedian said of the female flick that has raked in $105 million — and counting.

But the analyst also identified four star-laden comedies that didn’t work: “Baywatch,” “The House,” “Rough Night” and “Snatched.”

“It’s hard to stay fresh in the genre and easy to be perceived as derivative and exploitative,” he said.

The summer’s box office would have been normal had the movies singled out by Dergarabedian — the three tired tentpoles and the four failed comedies — met expectations.

“There’d be an extra $500 million in the marketplace,” he said.

That might have eased the pain caused by what The Guardian labeled the season’s epic fail — “King Arthur: Legend of the Sword.”

The Warner Brothers production had a US box office of $39 million on a budget of $175 million.

“The Dark Tower,” released on Aug. 4, rounds out the summer of discontent, with a Rotten Tomatoes rating of 16 percent.

“A complete disaster,” Hollywood trade The Wrap called it — much like the season itself.

Or, as Dergarabedian put it, “To be sitting on this big a deficit at the end of summer is almost unprecedented in its severity.”