A gang of hyperactive New Mexico high school kids faced down a sadistic serial murderer at the movies this weekend and came out on top, big time.

Disney's "High School Musical 3: Senior Year" -- the first installment of the 2-year-old franchise to graduate from cable TV -- recorded an estimated $42 million at the box office. The total was the best opening weekend ever for a movie musical, outpacing this summer's "Mamma Mia!" ($27.8 million) and last year's "Hairspray" ($27.5 million).

Lionsgate's "Saw V," the only thing in the U.S. offering more blood and gore than the stock market, pulled in an estimated $30.5-million weekend gross. For the "Saw" franchise, that marks a record four sequels in a row to open at more than $30 million -- particularly noteworthy given that the movies have been scheduled tightly, opening annually to tie in to Halloween each year.

For Disney, "HSM 3's" results came in at the "high end" of expectations, said Chris Leroy, the studio's executive vice president for domestic distribution. He said the studio had been a bit uncertain about how to gauge its potential, given that the first two entries in the franchise were cable TV movies. But Disney was banking on its high-spirited cast and upbeat scenario. "The minute the lights go down," he said, "the audience is ready to have a good time."

And get ready for "High School Musical 4." Although the core characters played by Zac Efron and Vanessa Hudgens are seniors in this installment, a whole new clutch of sophomores is being readied to carry the franchise ahead.

As for "Saw V," the moguls at Lionsgate are quaffing deeply from its pools of blood.

"It's a tremendous achievement to have four sequels in a row opening to $30 million-plus," said Steve Rothenberg, the company's president of domestic distribution.

He noted that the new installment's opening weekend record was only 4% behind that of "Saw IV" last year and that the series was already within a hair of supplanting "Friday the 13th" as the "highest-grossing horror franchise of all time," and will do so with only five pictures compared with the 11 produced by Paramount or New Line for the earlier franchise.

Indeed, the blood-soaked baton may already have been passed: The movie-tracking site Boxofficemojo.com calculates that as of Sunday morning the Saw films had already racked up lifetime gross box office of $316.3 million, ahead of the $315.6 million it shows for "Friday the 13th."

" 'Saw' is one of the most consistently performing franchises I've ever seen," said Paul Dergarabedian, president of box-office tracking firm Media by Numbers.

The two blockbuster franchise openings fueled a major lift for total box office this weekend, which brought in 35% more than the same weekend a year ago. That marks the fifth weekend in a row to exceed year-earlier totals, making Hollywood one of the few industries in the country with something to brag about these days. But year-to-date, theaters have taken in about as much this year as last, $7.7 billion, according to Nielsen EDI.

"High School Musical's" G rating and "Saw V's" R may have proved to be an ideal parlay this weekend to serve a wide spectrum of moviegoers.

"Ultimately, there was something for everyone in the marketplace," Dergarabedian said. "It shows that if you put the right movies in the market, people will turn out."

Filling out the top five this weekend were "Max Payne," a Fox production with an estimated $7.6-million gross, and Disney's "Beverly Hills Chihuahua," with $6.9 million, both holdovers from earlier openings. The No. 5 spot went to a Warner Bros.' newcomer, "Pride & Glory," a cop picture starring Edward Norton and Colin Farrell, with $6.3 million.