Critics were able to watch advanced screenings of the upcoming science fiction adventure movie "Valerian and the City of a Thousand Planets." Reviews have been mostly favorable with most critics appreciating the film's visual thrills and imagery.

"Valerian" currently has a 61 percent rating on RottenTomatoes, which is a site that aggregates reviews from various news and entertainment outlets. Bilge Ebiri of Village Voice wrote, "Valerian is at times so mind-meltingly beautiful and strange that I'm still not sure I didn't just dream it all."

From the trailer, the movie showcases impressive visuals of space worlds and alien creatures. It is based on the French science fiction comics series "Valérian and Laureline" written by Pierre Christin and drawn by Jean-Claude Mézières.

Luc Besson, who directed "The Fifth Element," "Léon: The Professional," and "Lucy," helmed "Valerian." The movie highlights the two lead characters: Valerian (Dane DeHaan) and Laureline (Cara Delevingne).

Some critics who praised the film's visuals and special effects did not favor the onscreen chemistry between the two lead stars, though.

Jim Vejvoda of IGN expressed, "['Valerian'] showcases plenty of cool creatures and ideas for sci-fi fans to savor, but if only the movie's central characters and their relationship were as exciting and interesting as all that impressive eye candy."

Meanwhile, Alonso Duralde of TheWrap wrote, "This is the kind of movie that soars beyond adjectives like 'good' or 'bad': it's sincere but overstuffed, visually gorgeous but dramatically clunky, and it represents a singular vision while simultaneously featuring two wildly miscast actors in the lead roles."

Valerian and Laureline are special operatives from the Ministry of Defense and are tasked to investigate a mysterious dark force that threatens the peaceful existence of the City of a Thousand Planets.

DeHaan's film credits include "Chronicle," "The Amazing Spider-Man 2" and "A Cure for Wellness." Delevingne is known for "Paper Towns," "Suicide Squad" and "Anna Karenina."

"Valerian and the City of a Thousand Planets" opens in cinemas on Friday, July 21.