The most generous thing you can say about “Based On A True Story”, Roman Polanski’s half-baked almost-thriller that screened out of competition at the Cannes Film Festival on Saturday, is that it goes down easy enough.

Banking on the director’s eyes-closed, hands-behind-his-back skill and a game cast of actresses, the film is an enjoyable if not terribly memorable jaunt. But consider the pedigree of cast and crew and make no mistake about it: That fully damns it with faint praise.

Polanski might well be the greatest living director of thrillers. Actress Emmanuelle Seigner, the star Polanski of successes like “Frantic” and “Bitter Moon,” once again takes center stage. She’s joined by Eva Green, who can marry femme fatale and camp queen like no other contemporary actress. (I mean this as the highest possible compliment.) And the film boasts a script written by Olivier Assayas, whose best work fuses the intellectual and the carnal with edgy aplomb. Every item was in place for this film to sizzle off the screen.

It really does not.

Also Read: 'Killing of a Sacred Deer' Cannes Review: Nicole Kidman, Colin Farrell Get Dark and Freaky

Seigner plays Delphine, a successful author still running victory laps from her last literary sensation while slowly confronting the fact that she has no idea how to start her next one. Onto the scene waltzes Elle (Green), a self-proclaimed super-fan who slowly and methodically burrows her way deeper and deeper into the older author’s life. Elle infiltrates Delphine’s social circle, and then her house, and then she begins cutting Delphine off from her friends and family.

You can sort of tell where the film is going, but “Based On A True Story” never actually gets there. If anything, the film is too timid, too unsure of what kind of story it wants to tell. Apart from a number of narrative dead ends and red herrings, Polanski (and Assayas, I suppose) never crack the dynamic between the actresses.

There are occasional flashes of erotic attraction, but they disappear as quickly and suddenly as they arrive. Is Elle a “Misery”-like super-fan, who thinks her fandom allows her to literally posses her favorite author? Or is she trying to steal some of the more famous woman’s spotlight for herself? The film has it both ways, and then, finally, neither.

Also Read: 'You Were Never Really Here' Cannes Review: Grim Joaquin Phoenix Puzzler Ends Competition

“Based On A True Story” ends with what you could call a plot twist, if the film would actually stand and own up to making a firm choice. Instead, the film just … ends, leaving the central relationship frustratingly unresolved.

There’s an elliptical insinuation that casts most of the film in a new light, but to make the most of it, you would have to dive back in and put the pieces together. And for the most part, once this entertaining if wafer-thin film comes to a close, it’s better to just turn a new page.

The 13 Tackiest Cannes PR Stunts, From Blake Lively's Sharks to Sacha Baron Cohen's Mankini (Photos)

From a faux terrorist attack to sharks in the French Riviera, promoters often miss the mark with their gaudy Cannes PR stunts.
Faux “Terror Raid” to Promote Oraxy
Guests at Hotel du Cap Eden-Roc got a surprise visit by men outfitted in militia-themed gear last year, who approached the hotel by boat. It was a publicity stunt for the Paris-based Oraxy, which describes itself as “the world’s first private global marketplace reserved exclusively for UHNWI,” or Ultra High Net Worth Individuals.
Sacha Baron Cohen Wears Green Mankini
In 2006, Sacha Baron Cohen sported a bright green male thong known as the “mankini” to promote “Borat! Cultural Learnings of America for Make Benefit Glorious Nation of Kazakhstan.”
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Sacha Baron Cohen Brings a Camel
In 2012, “The Dictator” actor turned up with two model bodyguards and a camel. He even managed to fall off the camel, which bore a license plate with “Wadiya 1” on it – a reference to the fictional North African Republic of Wadiya, where “The Dictator” was set.
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T.J. Miller Parachutes in to Debut "Emoji Movie" Trailer
To promote Sony’s “The Emoji Movie,” T.J. Miller parasailed into Cannes before unveiling a trailer for the film, in which he voices Gene, the Meh emoji. Emojis don't feel very Cannes.
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"The Shallows" Brings in Fake Sharks
To promote Blake Lively's nautical horror film, Screen Gems planted fake sharks in the French Riviera.

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Faux Snow for "A Christmas Carol"
Disney tapped Jim Carrey for a new version of “A Christmas Carol” in 2009 — and decided to bring the holiday spirit to Cannes by covering the Croisette with snow. Not the best example of reading the room or, in this case, the luxurious French beach town in the middle of May. Shout out to Robin Wright and Colin Firth in the background for looking horrified at the faux snowball fight.
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Jerry Seinfeld Flies In to Promote "Bee Movie"
In 2007, Jerry Seinfeld took Cannes by air to promote his big animated push for Disney, for which he served as writer and star and recruited pals like Chris Rock. His giant bee costume might have been worse than his notorious “Seinfeld” puffy shirt.
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Angelina Jolie, Will Smith Ride Inflatable Shark
Will Smith, Angelina Jolie and Jack Black rode a 14-foot inflatable shark to promote "Shark Tale" in 2004.
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"Trolls" Wigs
Anna Kendrick and Justin Timberlake promoted "Trolls" in 2016 with an array of women wearing bright-colored outfits and wigs reminiscent of the costumes in the movie. Also, they're all in gowns -- a play on Cannes fashion?
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Gaspar Noe’s Graphic Makeout Posters to Promote “Love”
Gaspar Noe at first shocked -- and then satisfied -- critics with his depiction of sex on film. He was praised for depicting the joyous and fervent act and staying mostly out of the realm of straight-up pornography. Promoting the film, however, was a different story. Producers wallpapered Cannes in posters of a saliva-covered triple kiss and an NSFW image of a penis and a woman's breast after climax.
Dolph Lundgren, Jean-Claude Van Damme Hold Impromptu Stage Fight
Both "Universal Soldier" actors held a stage fight on the steps of a famed staircase in 1992. Many believed it was real, but Lundgren told The Hollywood Reporter that it was planned.
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Dead pigeons for "24 Hour Party People"
In 2002, actors impersonating the band Happy Mondays mimicked a scene of the movie by throwing fake dead pigeons from the beach onto unsuspecting victims, who believed thousands of dead birds were falling from the sky, the BBC reported.
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Naked Bike Rides
Felix van Groeningen, the filmmaker behind “The Misfortunates,” decided to recreate a scene from his film where a dysfunctional family rides bikes in the nude. Just hours before a press conference, the director and his team disrobed and flew down the Croisette in the buff. A staffer on a motorcycle followed with their underwear, in case French police got a gander at them.
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