Mary's perilous move for her survival makes her realise that perhaps she is not the only one who may not survive. Elizabeth steadies herself for war and realises she and Mary might be more similar than either thought.
Mary struggles to survive childbirth, and Elizabeth discovers that someone in her inner circle caused the death of someone close to her.
A terrible tragedy pushes Mary and Darnley apart; Elizabeth is asked to support an expedition to the New World.
Mary pursues her quest for justice as she launches a counter-attack on her conspirators, and Elizabeth suffers a major setback that turns her world upside down.
Darnley and John Knox try to strip Mary of her throne. Elizabeth must banish Gideon from court at the request of her future husband, while Charles takes a bold stance against his brother Henri.