FEELY, Mont.—Helen Mirren had her shoes off and her feet propped close to a hissing propane heater. With co-stars Harrison Ford and Timothy Dalton she was huddled in a nook of a hollow building, a film set that looked like a stately stone-and-timber lodge on a snowy hill outside Butte, Mont. The actors were keeping warm while running dialogue for an outdoor scene they had tried in vain to shoot two days earlier, when subzero temperatures made it impossible for them to enunciate their lines.
