On her wedding day, Susan Murphy (voiced by Reese Witherspoon) is hit by a radioactive asteroid that causes her to grow into a 50ft threat to Mankind. Although she has no intention of harming anybody, and apart from her size feels much the same as she did before, the military cart her off to a secret location where she is incarcerated alongside other “monsters” from 1950s B movies. When Earth is invaded by the alien Galaxhar, who has detected the precious quantonium which now radiates from Susan, General W R Monger (Kiefer Sutherland) persuades the President (Stephen Colbert, possibly the best casting decision of the year) to unleash their top secret detainees as the planet’s last line of defense.

As Susan comes to terms with her new identity as Ginormica, the 50ft woman, she discovers an empowerment that had been missing in her previous existence. Wrestling a giant alien robot all over San Francisco allows her to see the inadequacies of her planned future, married to a local TV anchorman and opens up a world of opportunities her 1958 inspiration could have only dreamed of. In fact, over the course of the movie all of the “monsters” learn to embrace their identities and strengths and see beyond the fear and hostility they initially provoke in the general public.

The revolutionary new 3D technology used to make Monsters vs. Aliens has hijacked much of the film’s pre-release buzz. Dreamworks has moved away from the gimmicky in-yer-face three-dimensional trickery of yesteryear to create a more immersive and realistic viewer experience using cutting edge digital technology. Whether that in itself proves to be an audience draw remains to be seen, and cynics may see this proposed move towards 3D Cinema as little more than an effort to combat piracy, but suffice to say that it does enhance the enjoyment of an already entertaining film. What is abundantly clear is that beyond the pixels and the rendering and all the other technological bells and whistles, Monsters vs. Aliens is simply a damn fine piece of movie making that plays to a surprisingly broad demographic.

Time and effort have been made to create a story that is engaging and often very funny, lovingly harking back to McCarthy-era horrors such as the Communism, Feminism, Nuclear Proliferation and Alien Invasion, while never alienating those too young or disinterested to catch the references. The filmmakers are only too aware that the primary goal here is to entertain the young ‘uns while hopefully keeping the attention of their adult chaperones and in that respect the film succeeds almost without fault.

The motley crew of scientifically altered pariahs from a bygone era includes B.O.B. (The Blob), The Missing Link (The Creature from the Black Lagoon), Dr. Cockroach (The Fly) and Insectosaurus (Mothra), and all have been fleshed out by the writers beyond merely aping their legacy within popular science fiction. B.O.B. in particular, voiced by the increasingly omnipresent Seth Rogen, is hugely entertaining as the gelatinous mass without a brain. “It turns out you don’t need one!” he asserts gleefully. They have a gleeful camaraderie, resigned to their fate as “lifers” within their top secret military bunker and welcome Susan into their ranks with open arms. Even General Monger, their hard-nosed warden recognizes that these abominations of nature may yet have some redeemable qualities.

More than anything, however, it is obvious how much fun the animators had making Monsters vs. Aliens. The film never attempts to politicize its themes of invasion and paranoia or cast any kind of allegorical aspersions over the current state of the globe, but instead plays as a reverential tribute to the past half century of science fiction. From The Day the Earth Stood Still to Star Trek and E.T., the film is awash with references and knowing humour that should keep the more cine-literate viewers amused and entertained throughout. For younger audience members, raised on a healthy diet of Finding Nemo and Kung Fu Panda, the title is about as accurate a barometer as one should need. It’s Monsters vs. Aliens. What’s not to like? James Marsh