Mary (Adelaide Kane) becomes suspicious of Prince Don Carlos' (guest star Mark Ghanime) true condition and relies on Gideon (Ben Geurens) to help her uncover the truth. Elizabeth (Rachel Skarsten) makes a shocking discovery which could change the course of her reign over England and forces Dudley (Charlie Carrick) to make a tough decision. Meanwhile, Narcisse (Craig Parker) forces Claude (Rose Williams) to marry someone of his choosing, against her wishes.