GK Films has acquired rights to “The 5th Wave,” a proposal for a young-adult sci-fi book that is part of a planned trilogy from author Rick Yancey. Feature adaptation will also be produced by Tobey Maguire’s Material Pictures, with Sony Pictures the most likely to co-finance and distribute.Series follows a teenager who survives an alien invasion only to search for her brother, who may have been abducted by human-looking extraterrestrials. There’s also a romantic angle, as the heroine is helped by a boy who may also be an alien in disguise. GK Films principals Graham King and Tim Headington will produce with Maguire and Matt Plouffe.Jennifer Besser at Putnam Books for Young Readers preemptively purchased the book in a major deal for world English rights that was negotiated by Brian DeFiore of DeFiore and Co. Yancey’s 2009 young-adult novel “The Monstrumologist” was published by Simon & Schuster; the new manuscript is currently making the Hollywood rounds, with CAA handling film rights. GK recently teamed with Maguire on Gary Ross’ sci-fi action film “Outback,” which has Carey Mulligan attached to star.