Warner Bros. has tapped “Apollo 18” scribe Brian Miller to take a crack at “Rome, Sweet Rome,” a high-concept time travel story that originated from the website Reddit.com.

In October 2011, Warners preemptively purchased the “Rome, Sweet Rome” pitch from first-time scribe James Erwin, an author and two-time “Jeopardy!” champion from Des Moines, Iowa. Erwin’s pitch sale sprang from several postings on Reddit, an online community and social news aggregator where he set out to answer the question: “What if a unit of U.S. Marines are transported back in time and forced to do battle with Roman legions?”

Madhouse Entertainment’s Adam Kolbrenner spotted Erwin’s “Rome, Sweet Rome” posts once they were voted to the Reddit home page and moved quickly to contact the writer and begin working with him to develop the concept. When it came time to find a home for the project, Kolbrenner brought it to WB exec Chris Gary, who encouraged the studio to move aggressively to acquire it.

Erwin ended up writing a draft of the screenplay, but the studio felt it needed a fresh approach — which is where Miller, who never saw Erwin’s draft, comes in. Latest logline only slightly tweaks the original, however, pitting “U.S. Special Forces,” as opposed to Marines, against Roman warriors.

Kolbrenner and Madhouse will produce with Gianni Nunnari of Hollywood Gang and Safe House Pictures duo Tory Tunnell and Joby Harold, the latter of whom was instrumental in coming up with how the concept can work for WB. Madhouse’s Robyn Meisinger will exec produce.

Miller’s “Apollo 18,” a low-budget, star-free, found-footage sci-fi pic, grossed a surprising $17 million Stateside for The Weinstein Co in 2011. In addition to “Rome, Sweet Rome,” Miller has also been working with “American Horror Story” co-creator Ryan Murphy on an untitled sci-fi/horror movie for Sony Pictures and producer John Palermo (“Drive”), as well as an untitled sci-fi thriller for Paramount and producer Brad Weston.

Miller is repped by CAA, 3 Arts Entertainment and attorney Lev Ginsburg.