The Crown quickly abandoned plans to turn Olivia Colman's eyes blue to match Claire Foy's eye color

Variety

The brown-eyed Colman was initially fitted with blue contact lenses to match Foy's eye color, according to The Guardian. But director Ben Caron says it made Colman seem like "she was acting behind a mask. It was as if we had taken all of her acting ability and put it in a safe and locked it away.” They also tested turning her eyes blue in post-production. “But it didn’t feel like her," he says. "CGI-ing her eyes seemed to diminish what she was doing.”