SOME cartoon characters evolve into fully-realised, three-dimensional protagonists when liberated from the page - Tom Holland's adolescent Spider-Man, for example.
Others, such as space and time travelling special agent Major Valerian (Dane DeHaan) and his willowy offsider Laureline (Cara Delevingne), are unable to break free of their comic book constraints.
The blankness of these two central performances sets the tone for Valerian and the City Of a Thousand Planets, a visually-arresting sci-fi mashup directed by Luc Besson (Lucy, The Fifth Element, La Femme Nikita).
Some of the dialogue - particularly in relation to a suggested but indiscernible sexual attraction between the pair - falls awkwardly flat.
But the actors' emotional detachment is not altogether a bad fit for such a surreal backdrop.
Clive Owen's theatrical take on their overbearing commanding officer, Arum Filitt, is much more jarring, by comparison, admittedly in a thanklessly underwritten role.
Rihanna literally stops the show as a shapeshifting erotic dancer who performs for Major Valerian in The City Of a Thousand Planets' gaudy red-light district Pleasure Alley.
While the Grammy award-winning singer's non-sequitur performance is a mistake in terms of pacing, it's an entertaining digression nonetheless. And there's a cheeky cameo from Ethan Hawke as her pimp.
Paradise Alley is a world apart from the planet Valerian sees in his opening apocalyptic dream - about the destruction of a pastel island paradise inhabited by luminescent creatures who exist in perfect harmony with their planet, fishing for energy-rich pearls that they replicate with the help of tiny reptilian creatures known as "converters".
In a strange coincidence, Valerian and Laureline are then directed to retrieve one of these rare creatures from a black market dealer - a mission that results in against-the-clock chase sequence through the alternative dimensions of a desert-based souk.
Escaping in the nick of time, they transport the converter back to The City Of a Thousand Planets, where Owen's Commander Filitt is battling a mysterious radioactive threat that has the capacity to destroy the trailblazing space station.
It's not long before the arse-kicking pair smells a rat - and they set out to investigate alone.
Valerian and the City Of a Thousand Planets is based on a French comic book series published in the 1960s and '70s, which Besson identifies as a major influence on George Lucas.
The parallels between Besson's film and Lucas's seminal space opera are certainly clear.
Valerian and the City Of a Thousand Planets plays like a psychedelic joy ride through the cinematic universe - with nods to Star Wars, Blade Runner and Avatar amongst others.
But it lacks any kind of narrative compass. A space traveller who plotted his course with as little attention to the laws of the cosmos would surely meet a sticky, solitary end.
Valerian and the City Of a Thousand Planets is in cinemas today.
Valerian and the City Of a Thousand Planets
Stars: Dane DeHaan, Cara Delevingne, Clive Owen, Ethan Hawke, Rihanna.
Director: Luc Besson
Verdict: 2.5 stars
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