Reviews could signal a 'Fantastic' flop for Fox

Fantastic 4 movie poster.
Source: 20th Century Fox

The lead up to 20th Century Fox's "Fantastic Four" reboot has been anything but smooth. The production has been plagued by reports of an isolated and erratic director, fan outcry over leaked script details and heated online debates about the decision to cast an African-American actor as a Caucasian character.

But what really raised alarm bells was Fox's choice to embargo reviews until the day before the movie's U.S. premier. With "Fantastic Four" opening Thursday night, the results are in—and they're ugly.

"Fantastic Four" currently ranks as the worst reviewed movie featuring a Marvel property on critic aggregation website Rotten Tomatoes. As of Thursday afternoon, the film carried a 8 percent rating out of a possible 100 percent, based on 49 reviews.

That's worse than the 10 percent rating for the 2005 "Daredevil" spinoff and box office bomb "Elektra." Even 1986's "Howard the Duck" garnered kinder aggregate reviews, beating "Fantastic Four" by 5 percentage points.

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The film is Fox's second stab at bringing Marvel's quartet of super-powered heroes to life. The studio shelved the franchise after two installments in 2005 and 2007 failed to capture moviegoer imaginations.

Eric Henderson of Slant called the new film, "So appallingly dull that even a third-act parade of exploding heads can't rouse interest." The Miami Herald's Rene Rodriguez said, "the picture has the uneven tone of the work of someone who was in way over his head and lost sight of the picture he was making."

Reviews like those prompted to lower its forecast for the film's opening weekend for a second time to $43 million. Last week, it revised down its projection from $50 million to $46 million based on middling social media buzz and unexpectedly positive word of mouth for "Mission Impossible - Rogue Nation," which opened last weekend and stands to steal Fox's thunder.

"Fantastic Four" cost Fox $120 million to make, not including marketing expenses, according to trade journals. Fox did not respond to requests for comment.

Paul Dergarabedian, senior media analyst at Rentrak, said he still expects "Fantastic Four" to dominate the weekend, but the film's ultimate success is up in the air.

"[A]ny Marvel fan who was planning to see the film will not be influenced by reviews; they will still go to see the film for themselves," he told CNBC in an email. "Of course the long term prospects for 'Fantastic Four' will rely on the reaction to the film by the peer group of fanboys and fangirls via social media. ... They are the true influencers."

To be sure, Fox has scored a number of moderate hits this year with films made on relatively low budgets, including the Melissa McCarthy comedy "Spy" and the animated feature "Home."

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But a "Fantastic Four" flop would not bode well for Fox at a time when it is ramping up its slate of films featuring Marvel properties.

Fox is scheduled to release three Marvel films next year, including the sixth installment of its core X-Men franchise, "X-Men: Apocalypse." The others—"Deadpool" and "Gambit"—feature fan favorite characters that are thus far unproven at the box office. (Versions of both characters appeared in the little-loved "X-Men Origins: Wolverine.")

And then there's its 2017 superhero slate, which currently includes "Fantastic Four 2."

The reviews are almost sure to reignite the debate about whether studios that own right to Marvel Comics characters are better off collaborating with Walt Disney-owned Marvel Studios, which has turned out 12 hits in a shared cinematic universe.

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Earlier this year, Sony announced it would develop a second reboot of its Spider-Man franchise in partnership with Disney and allow the web-slinger to appear in the House of Mouse's "Captain America: Civil War." The question is whether Marvel and Disney can better steer the "Fantastic Four" to success.

Disclosure: 20th Century Fox competes with Comcast-owned NBCUniversal, parent company of CNBC.