Chronicling the outbreak of a global pandemic, Contagion is a lot like the virus it depicts, surging through your bloodstream and into your brain, wracking you with fear, paranoia and moral indecision. Bolstered by a practically inconceivable cast, director Steven Soderbergh weaves multiple storylines — not dissimilar to his 2000 Oscar-winning drug drama Traffic — in order to show the effects of the disease on various levels of society. Succeeding on both a micro and macroscopic level, this is a smart, scintillating, all-too-credible medical disaster movie that provokes thought and terror in equal abundance.

The disease appears to begin with a suburban Minneapolis woman (Gwyneth Paltrow; Iron Man 2), who returns home from a trip to Hong Kong only to fall fatally ill. Her husband (Matt Damon; The Adjustment Bureau) is put into quarantine by a doctor from the Centre for Disease Control (Kate Winslet; Revolutionary Road) on orders from her superior (Laurence Fishburne; Predators), but it soon becomes clear the virus is spreading at rate faster than they can contain it. CDC scientists led by Dr. Ally Hextall (Jennifer Ehle; The King’s Speech) scramble to find a vaccine, while a representative from the World Health Organization (Marion Cotillard; Inception) attempt to discover the origin of the disease. As social order begins to collapse, the public’s fear and mistrust is fanned by conspiracy minded bloggers like Alan Krumwiede (Jude Law; Sherlock Holmes), who push the agenda of money-minded pharmaceutical companies.

What makes Contagion so effective is its sense of plausibility. One can only imagine how much meticulous research screenwriter Scott Z. Burns put into his script; the film makes frequent reference to previous health scares like bird flu and H1N1, presenting itself as the ultimate “what if?” scenario. In one scene Winslet’s character offers a basic explanation of how the virus works and spreads, as Burns successfully walks the line between making the movie understandable to audiences without seriously diluting the science. In another moment of disturbing pragmatism, CDC officials discuss the difficulties of manufacturing and distributing a vaccination in the event that one is even discovered.

The authenticity extends beyond the medical speak, as Burns and Soderbergh offer fascinating insight into all the social elements that would likely come into play. Bureaucrats bicker over the financial concerns of setting up relief centres, while military advisors panic at the idea that the disease might have originated as a biological weapon. There are references to the dissemination of rumours and misinformation via Facebook and Twitter, as the film expertly explores the ways in which fear might be spread in this information age; fear which soon turns to chaos, as frightened civilians turn on each other in the fight to stay alive.

Yet even as the movie documents the large scale social reaction to the virus, it also manages to maintain a remarkable intimacy. Even as the world collapses around him, Matt Damon attempts to give his wife a proper burial, while also providing some semblance of normalcy for his sixteen year old daughter. Lawrence Fishburne takes time to mourn the passing of a colleague, and at a later point makes a decision that forces the audience to ask difficult ethical questions of themselves.

While Soderbergh certainly has a knack for putting together fantastic ensembles, he also knows how to use them. Each A-list performer is at the top of their game, ensuring that even with the limited screen time they may receive, their characters and storylines never feel short-changed. Meanwhile, almost the entire secondary cast is filled with fantastic character actors including Bryan Cranston (TV’s Breaking Bad), Enrico Colantoni (TV’s Veronica Mars), Elliot Gould (Oceans 11) and John Hawkes (Winter’s Bone).

Soderbergh, ever the stylistic chameleon, makes fantastic use of the docudrama style to further enhance the movies’ dogged sense of realism. The raw chill of the digital cinematography contributes to the tense, paranoid quality that permeates the film, something which is further enhanced by lingering shots of glasses, doors and railings; constant reminders of an invisible threat. His use of montage, too, is especially effective at driving the expansive story forward, all the while accompanied by Cliff Martinez’s brilliant electronic score.

Compelling and terrifyingly real, Contagion balances its multitude of characters, scenarios and fascinating ideas with steadiness and lethal efficiency. It is hard to imagine anyone walking out of the film unaffected, either intellectually, viscerally, or both. At the very least, it will make you think twice the next time someone offers you their hand in greeting. Social conventions be damned; you never can be too careful when it comes to your health.

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