UPDATE SUNDAY, 8:17 a.m.: Conventional wisdom holds that you don’t release sequels two decades apart, particularly in a lightning-bottle genre like comedy. But wisdom has never held much sway in the Dumb and Dumber franchise, which returned after a two-decade dormancy to engage in a nip-and-tuck battle with Big Hero 6 that underscored the muscle of raunch this year at the box office.

Dumb and Dumber To looked to take the derby this weekend from a BH6 in its sophomore frame, though Hero’s repeat-viewing younger audiences could still propel it to a follow-up victory when actuals are reported Monday. Still, Universal turned its $30M DDT into a contender with a “deja-view” strategy that worked the last time Jim Carrey and Jeff Daniels got together: gross-out audience, out-gross competitors.

And the studio played up the nostalgia, returning the stars to their bowl cuts, gapped teeth and slack-jawed expressions for the reunion (though it’s actually the third DDT film; Dumb and Dumberer: When Harry Met Lloyd flunked with $26.2M in 2003).

DDT proved savvier, if not to critics, who gave it just a 27% rating on Rotten Tomatoes. But the franchise has never concerned itself with critical response, and, for a low-brow comedy, its B- CinemaScore actually suggests some word of mouth power among its young-skewing viewers (53% of whom had seen the original on home video). The original opened to $16.3M two decades ago.

“This was tricky to market,” said Universal distribution chief Nikki Rocco. “A lot of these kids weren’t born when the first (film) came out. But it has been such a serious time in movies, we had great marketing, mindless humor, and we broadened the audience.”

In their second frames, BH6 and Interstellar revived their tete a tete with solid holds, though Interstellar again played bridesmaid to Disney’s mega cartoon. If estimates hold, both movies will have dropped less than 40%, sending BH6’s domestic cume north of $111M. The 169-minute Interstellar will cross the $100M mark, thanks largely to its sizable IMAX presence. Disney crossed the $4B mark internationally, on the second time the Mouse House has reached that very big milestone. Our Nancy Tartaglione has more in her international box office report.

Opening on 1,789, the cop-singer romance Beyond the Lights met the low end of expectations and captured fourth place. While the numbers weren’t eye-popping, the first movie under Relativity’s new multicultural division landed an A CinemaScore and an 84% on CinemaScore, which positions the $7M pic well through Thanksgiving. And David Fincher’s Gone Girl needs to sign a long-term lease with the box office, because it won’t move from the top five.

Among the indies, Jon Stewart’s Rosewater has a solid-if-unspectacular debut, taking about $3,200 per screen. The Theory of Everything, meanwhile, continues its strong averages. The Stephen Hawking biopic expanded to 41 screens and averaged $18,000 per. And the real-life crime drama Foxcatcher, starring Steve Carell and Channing Tatum, caught a whopping $45,000 per screen in only six theaters.

Perhaps the bigger news on the specialty side might be with Birdmanwhich looks like it will crack the top 10 five weeks into its release and after a big expansion to 857 theaters. The film is headed to a $2.4 million weekend, with a three-day average of $2,850, and has grossed $11.5 million so far. The drama about a washed-up superhero actor seeking Broadway critical redemption isdirected by Alejandro Gonzalez Inarritu. It stars Michael Keaton, Edward Norton, Naomi Watts and Emma Stone. For more specialty box office, make sure to check out Brian Brooks’ analysis.

1). Dumb and Dumber To (UNI), 3,154 theaters / $14.2M Fri./ $13.86M Sat. (-2%)/ $8.3M Sun. (-40%)/ 3-day cume: $36.3M / Wk 1

2). Big Hero 6 (DIS), 3,773 theaters (+12) / $7.9M Fri. / $16.5M Sat. (+108%) / $11.45M Sun. (-30%) /3-day cume: $35.8M (-36%)/ Total Cume: $111.4M /Wk 2

3). Interstellar (PAR), 3,561 theaters (0) / $8.3M Fri. / $12.45M Sat. (+50%) / $8M Sun. (-36%) / 3-day cume: $28.7M (-38%) / Total cume: $97.4M / Wk 2

4). Beyond the Lights (REL), 1,789 theaters / $2.3M Fri. / $2.6M Sat. (+15%) / $1.4M Sun. (-45%) /3-day cume: $6.4M / Wk 1

5). Gone Girl (FOX), 1,959 theaters (-265) / $1.3M Fri. / $2.1M Sat. (+59%) / $1.1M Sun. (-45%) / 3-day cume: $4.6M / Total cume: $152.6M / Wk 7

6). St. Vincent (TWC), 2,332 theaters (-123) / $1.1M Fri. /$1.7M Sat. (+55%) / $1.1M Sun. (-35%) / 3-day cume: $3.9M / Total cume: $33.2M / Wk 6

7). Fury (SONY), 2,382 theaters (-452) / $1.1M Fri. / $1.65M Sat. (+50%) / $1M Sun. (-35%) /3-day cume: $3.8M / Total cume: $76M / Wk 5

8). Ouija (UNI), 2,382 theaters (-298) / $1K Fri. / $1.4M Sat. (+39%) / $630K Sun. (-55%) /3-day cume: $3M / Total cume: $48.1 M / Wk 4

9). Nightcrawler (OPRD), 2,103 theaters (-663) / $902K Fri. / $1.2M Sat. (+33%) / $765K Sun. (-40%) /3-day cume: $2.8M / Total cume: $24.8M / Wk 3

10). Birdman (FSL), 857 theaters (+397) / 697.5K Fri. / $1.1M Sat. (+60%) / $669K Sun. (-40%) /3-day cume: $2.4M / Total cume: $11.6M /Wk 5

Noteworthy:

Rosewater (OPRD), 371 theaters / $391K Fri. /$412K Sat. (+5%) / $268K Sun. (-35%) / 3-day cume: $1.05M/ Wk 1

Foxcatcher (SPC), 6 theaters / $75K Fri. / $115K Sat. (+53%)/ $80K Sun. (-30%)/3-day cume: $275K ($45K per screen avg.)/Wk 1