Amy McAllister is an actress most notable for her role as Mary in hit BBC drama Call the Midwife. She recently appeared in the third series …Amy McAllister is an actress most notable for her role as Mary in hit BBC drama Call the Midwife. She recently appeared in the third series of Witless (TV series) on BBC Three. Amy can also be seen in the Stephen Frears film Philomena, which stars Steve Coogan and Judi Dench.