NEW YORK  — In a weekend of perfect counterprogramming for Hollywood, the comic-book movie “Venom” shrugged off bad reviews to shatter the October box-office record with an $80 million debut, while Bradley Cooper’s “A Star Is Born” soared to $41.3 million.

With $174.5 million in tickets sold at U.S. and Canadian theaters, according to comScore, it was easily the best October weekend ever thanks to two very different films that both outperformed expectations.

“Venom” came in a critically panned, much-doubted foray by Sony Pictures to kick-start a Marvel expansion away from “Spider-Man.” Warner Bros.’ “A Star Is Born” remake rode a wave of hype, Oscar buzz and acclaim for Cooper’s directorial debut and Lady Gaga’s first leading performance.

One was a very iffy proposition; the other a sure thing. Both worked big time.

“We knew we had a hit,” said Warner Bros. distribution chief Jeffrey Goldstein of “A Star Is Born.” ‘’We also knew that every time people saw the movie, they felt it, they cried, they loved it. People just like the movie.”

That was more in question for director Ruben Fleischer’s “Venom,” starring Tom Hardy as the antihero who first appeared in 2007’s “Spider-Man 3.” The film earned a dismal 32 percent “fresh” rating on Rotten Tomatoes. In “Venom,” many expected another studio misfire with “cinematic universe” ambitions.

Yet audiences flocked to “Venom” in record numbers, giving it a B-plus CinemaScore. The previous best October opening was 2013’s “Gravity” with $55.7 million (not adjusted for inflation).

Adrian Smith, president of domestic distribution for Sony, said that even though the studio was confident, “I did not see $80 million coming.”

The most telling number that explained the film’s success, Smith said, was the 89 percent “fresh” audience score on Rotten Tomatoes. “Venom,” which cost about $100 million to make (relatively modest for a superhero film), grossed a total of $205.2 million globally.

Steven O’Dell, Sony’s president of international distribution, said the studio wanted to carve out a new approach for the comic-book adaptation with the PG-13-rated “Venom.”