Contagion is the latest in a line of medical horror thrillers involving communicable diseases. There have been many previous films, including the 1995 film Outbreak, starring Dustin Hoffman and Rene Russo, various zombie films, and even Rise of the Planet of the Apes, still in theaters, ends with a highly contagious virus being spread around the world, conveniently setting the stage for the sequel.
The question is not, ‘Has this movie been done before?', because the obvious answer is yes. Disaster films are nearly as formulaic as romantic comedies: There are only so many ways you can get from Plot Point A to Plot Point Z. All Contagion-like films feature similar stock characters: the heroic scientists who valiantly strive to save the day; the authoritarian government officials who impose martial law ostensibly for the greater good; the hero who swears he's not infected; and so on.
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The first half of the film seems promising, but sputters and finally loses its way under the weight of a bloated cast and their scattered subplots. It's great to have so many good actors in a cast (Gwyneth Paltrow, Laurence Fishburne, Kate Winslet, Jude Law, Matt Damon, etc.), but the problem is giving them all a big enough role to merit their involvement (and paychecks). Soderbergh can frame his shots with the best of them, but when it comes to the story he doesn't seem sure what to focus on, so we jump back and forth among various storylines, some of them interesting, others half-baked.
For example Jude Law appears as a conspiracy theorist blogger nutjob who advocates a worthless homeopathic remedy instead of a proven vaccine to combat the disease, and by the time a CDC worker is kidnapped and held for ransom (though her absence is apparently not noticed for weeks), the film's credibility is in tatters. (Even less explicably, the last time we see her in the film she's apparently running through an airport to help her kidnappers.) I strongly suspect that there were interesting stories about these characters that were left on the editing room floor due to time constraints. Soderbergh should have requested a tighter rewrite instead of trying to cram everything in. Soderbergh finally gives up on trying to follow the genesis of this contagion, and the epidemiological detective story of how exactly the virus came into being isn't revealed until literally the last few minutes of the film, more or less as an afterthought.
http://www.centerforinquiry.net/blogs/entry/contagion_film_review--_now_with_20_more_anti-vaxx_conspiracy/