S3, E3: When King Antoine (guest star Ben Aldridge) unexpectedly returns to Court, Mary (Adelaide Kane) must help Francis (Toby Regbo) hide his weakening condition long enough to secure his family's future. With the Throne in jeopardy and time running out, they must turn to an unlikely ally in need of redemption. Megan Fellows, Anna Popplewell, Craig Parker, Torrance Coombs, Celina Sinden, Jonathan Keltz and Rose Williams star.