'Reign' Season 4 Episode 6: Is Mary Prepared to Go to War for Lord Darnley?

(Photo: YouTube/The CW)A screenshot from the promo for "Reign" season 4, episode 6 season 4, "Love and Death."

Queen Mary (Adelaide Kane) faces a new problem as she pushes for marriage with Lord Darnley (Will Kemp) in "Reign" season 4, episode 6, "Love and Death."

After proving himself in a boxing match at the Highland Games, Lord Darnley not only wins over the approval of the Scottish nobles by besting Lord Taylor, he also won Mary's heart.

A new threat to the marriage emerges in "Reign" season 4, episode 6 with the English on the way and Elizabeth (Rachel Skarsten) doubling down her efforts to stop the union.

Defying the English would mean warfare. James (Dan Jeannotte) reminds Mary that in the promo, but she already knows what this marriage could bring.

"You need to decide if this marriage is worth it, because the English are coming and if you defy them," James tells his sister, who finishes the sentence for him, saying "It would be war."

Mary appears to be adamant in making this marriage happen. It looks like it is not just about securing the throne anymore as she appears to be genuinely into Lord Darnley. The promo for "Reign" season 4, episode 6 shows the two locking lips.

The Queen of Scots knows the stakes that come with the marriage and it seems that she is not charging into it without a plan. Whatever scheme Elizabeth has in motion, Mary is expected to counter.

As all this happens, "Reign" season 4, episode 6 will also see Catherine (Megan Follows) continue to clean up the mess brought about by the erratic behavior Charles (Spencer Macpherson) has been exhibiting.

The King is not doing a good job at winning over their people, who now believe he is a murderer. To make things worse, he disappears on his mother in this installment. In turn, she is left to deal with the aftermath of his actions.

"Reign" season 4, episode 16 will also see Claude (Rose Williams) receive an "interesting proposition," per the synopsis for the episode.

Last week's installment saw Claude try to convince Leith (Jonathan Keltz) that she let her and Luc (Steve Lund) stay married, provided it is an open marriage.

This way, Claude and Leith can still be secretly together, but the latter is not at all for sharing Claude, but the princess believes there is no other choice.

It is unknown what sort of proposition she gets in "Reign" season 4, episode 16, but it is expected to get things decided between her and Leith.

"Reign" season 4, episode 16, "Love and Death," airs Friday, March 24, at 9 p.m. ET on The CW.