In a pre-emptive purchase, 20th Century Fox has acquired S.J. Kincaid’s futuristic young adult thriller “Insignia.”Book is the first in a planned trilogy. Set during World War III, story centers around a 14-year-old gamer who enrolls in an elite military training academy. Before long he discovers that the military intends to turn him into a superhuman fighter by installing a computer in his brain. “Insignia” marks Kincaid’s debut novel. The author sold her three-book series to Harper Collins last year for between $250,000 and $500,000, according to online database The Publishers Marketplace. Peter Kang will oversee the project for Fox. Harper Collins will publish “Insignia,” which hits stores July 10.