In the 28th century, the former International Space Station has been added to until its mass threatens to cause it to fall out of orbit. Relocated to deep space, it becomes Alpha, a space-traveling city inhabited by millions of creatures from thousands of planets. A special police division is created to preserve peace through the galaxy, including happy-go-lucky Major Valerian and his partner, no-nonsense Sergeant Laureline.
Valerian hands over the pearl he stole, and Laureline persuades him to return the converter too, ignoring procedures. While the Pearls' spacecraft prepares for takeoff, the other species in Alpha, Filitt's pre-programmed robot K-Tron Soldiers attack the Pearls, the government Soldiers who were sent to assist Valerian, and their support staff, but are ultimately defeated. The spacecraft departs and Filitt is arrested. Valerian and Laureline are left adrift onboard a still working Apollo Command/Service Module, which is identified by radio technicians as "Destiny 2005", and Laureline finally accepts Valerian's marriage proposal as they wait for rescue.
Valerian received mixed reviews from critics, who praised its visuals while criticizing the plot and some of the casting. On review aggregation website Rotten Tomatoes, the film has an approval rating of 49% based on 237 reviews, with an average rating of 5.5/10. The site's critical consensus reads, "Valerian and the City of a Thousand Planets uses sheer kinetic Energy and visual thrills to overcome narrative obstacles and offer a viewing experience whose surreal pleasures often outweigh its flaws." On Metacritic, which assigns a weighted average rating to reviews, the film has a score of 51 out of 100, based on reviews from 45 critics, indicating "mixed or average reviews". On French entertainment information website AlloCiné, the film has an average grade of 3.0/5, based on 31 critics. Audiences polled by CinemaScore gave the film an average grade of "B–" on an A+ to F scale.
The project was first publicly reported in 2012. The two principal stars, Dane DeHaan and Cara Delevingne, were announced in May 2015. On 19 August 2015, Clive Owen signed on to play Commander Arün Filitt in the film. The budget, €197 million, is by far the largest ever assembled for a French film. Previously, Asterix at the Olympic Games was the most expensive, at €78 million, just ahead of Besson's The Fifth Element (€75 million). By the end of August 2015, Besson said in an RTL radio interview that shooting the film in France was too expensive. Because it was filmed in a foreign language (English), Besson was unable to benefit from tax credits, despite preferring to produce the film in France and create jobs for 1,200 crew members. The criteria to obtain these tax credits were then adapted accordingly. In May 2015, it was announced Fundamental Films would invest US$50 million in the film.
The first teaser for Valerian was released on 10 November 2016. The teaser depicts Marmakas, Entertainers, Bagoulins, and Shingouz, who all appear in Ambassador of the Shadows. A special exclusive preview of Valerian was shown prior to the Fathom Events 4K restoration showing of The Fifth Element on 14 May and 17 May.
Todd McCarthy of The Hollywood Reporter gave a negative review, saying: "The Razzies don't need to wait until the end of the year to anoint a winner for 2017 ... Hollywood studio chiefs can breathe easy that, this time, at least, they'll escape blame for making a giant summer franchise picture that nobody wants to see, since this one's a French import." A. O. Scott of The New York Times was also less than happy with the film, writing the effort "feels as if it were made up on the spot, by someone so delighted by the gaudy genre packaging at his disposal that he lost track of what was supposed to be inside." National Public Radio film critic, Mark Jenkins, additionally wrote in a negative review that the film's "perspective often seems more 19th- than 26th-century, notably in a sequence where Laureline is captured by members of a hostile species and forced to don a white dress to be presented to their Emperor. The blobby computer-generated creatures resemble natives from the most racist of Tarzan movies."
David Ehrlich of IndieWire gave the film a grade of B-, praising how "unapologetically idiosyncratic" the film is, while also saying "the vividness of this place only underscores the lifelessness of the people leading us through it .... There are 394 million stories on the City of a Thousand Planets, and Valerian’s might be the only one we’ve seen before. Still, any excuse to visit this place is one worth taking." Peter Sciretta of /Film touted the first half of Valerian as "unpredictable and bonkers insane", while calling the second half more formulaic and "far less exciting", though he still encouraged seeing the film in 3D "on the biggest screen possible". Ignatiy Vishnevetsky of The A.V. Club wrote that it was "rare […] to see a film this extravagant that also feels, for better or worse, like the work of a single personality. The longer action scenes may not always rank with Besson’s early ’90s highlights [...] or the mania of the more recent Lucy, but there isn’t a moment in this ludicrous, lushly self-indulgent movie that doesn’t feel like its creator is having the time of his life."