An astronomer detects evidence of intelligent alien life, only to find himself encountering it all too closely.
Scientist Charlie Sheen picks up what he thinks is a signal from a distant star and promptly finds himself out of a job, discredited, dumped by girlfriend Polo and on the run in Mexico.
In a subtle homage to (a.k.a. blatant steal from) the plot of Quatermass II, it turns out that aliens who want to take over the earth have taken over key government positions and are upping industrial pollution all over the globe to the point where they can breathe more easily.
Sheen runs into various sinister or helpful individuals, some of whom naturally betray him, and makes that familiar 1970s-style dash to expose the big story in the press.
Though the plot is nothing new and the big alien effect looks unfortunately silly, The Arrival has some nice set pieces: an opening with scientist Grouse pottering about a lush field that turns out to be a tiny patch of unnatural green in Arctic wastes, a descent into an alien installation where Sheen steps into the device that enables E.T.'s to pass for human and is turned into a Mexican, and a whirling implosion-bomb that allows for a spectacular finale.
No masterpiece, but a decent rental prospect. Twohy works the Sci-fi genre well yet again.