Barbara Masterson, who lives on a farm at the top of a small mountain in the southern Ulster hamlet of Milton, had always painted landscapes. But one day in May 2015, when she was out painting on a neighboring farm in Marlborough, some migrant workers wandered into the scene and her subject began to change. “I just painted them in quickly,” she said. “It was kismet. I was just innocently painting and they just kind of appeared.”