Mary tests her brother after he meets with John Knox, because she's unsure about whom she can trust. Meanwhile, Elizabeth schemes to sabotage Lord Darnley's relationship with Mary.

Cast: Adelaide Kane, Megan Follows, Rachel Skarsten, Celina Sinden, Craig Parker, Rose Williams, Ben Geurens, Dan Jeannotte, Jonathan Goad, Spencer Macpherson, Will Kemp, Anastasia Phillips, Lewis Kirk, Stewart Arnott, Nola Augustson