The Eagle is an engaging, if straightforward and one-dimensional, quest tale set in the wilds of northern Britain during Roman times. Based on a 1954 best-seller by the late Rosemary Sutcliff, one the last century's most popular English authors of books for young readers, this story of colliding cultures and lost honor regained is more intimate and less brutal than most period epics made these days. But while this Eagle may fly in the U.K. and some other international markets, prospects for this PG-13-rated Focus release look iffier domestically, where adult audiences may find it simplistic and teens may not sense enough fun or action within to check it out.