The dark animation series was originally screened in three-minute episodes in Britain, but Rowntree and co-creators Ant Cauchi and Lloyd Salmons will now produce 30-minute shows tailored to an American audience.
Rowntree says, "We wouldn't have been happy in kids' TV - you can't be nearly disgusting enough. We've got kind of an evil sense of humour, really. I think the main amount of tinkering we need to do is to ramp up from a three-minute show.
"Obviously we can't make jokes about specifically English things that Americans won't understand. But there's a kind of satire to what we do, so we have to be reasonably topical."
Empire Square focuses on characters RABBIT, HOOKS and RICHIE as they try to become pop superstars.