'Reign' season 4 spoilers: a character gets 'really crazy'; Mary tries fencing

"Reign" season 4 will give fans plenty of reasons to worry about the fate of a character, one of which involves deteriorating health, as revealed by lead star Adelaide Kane herself.

In an interview with Melty, the actress spilled the beans on someone's fate this season. "Someone falls sick. Someone in the new season, falls ill and becomes crazy, as King Henri II," she teased, as per the translation of a fan with the Twitter handle NotDoneAbusingU.

Kane continued to played coy, "I can't tell you who, otherwise I'll get into trouble, but someone gets really crazy." It looks like fans will have to wait for "Reign" season 4 to learn who it is.

As for her character, Mary will be working hard to keep her power intact in the final season of the historical drama. In the process, she develops trust issues and loses many of her allies.

Kane says Mary is "growing very quickly" in "Reign" season 4. "She's trying desperately to follow the choices she made. Some of the choices she made are not the wisest and she will be questioning again," she explained.

"There will be a sort of power struggle between her and Lord Darnley (Will Kemp) and even more than before the difficulty of being a woman in power with the men who are trying to take it from her," she went on to say.

For the uninitiated, Lord Darnley is a new character in "Reign" season 4. He will be Mary's new husband, but their relationship is "very fun but also very problematic."

Also, in Mary's efforts to stay in power in "Reign" season 4, she will also be doing more this time. According to TVLine, a different side of the queen will be shown in the premiere and it involves sweat and violence.

Early this month, it was teased by Entertainment Weekly that she will be doing some fencing so it appears that Mary will take part in some fighting this season.

"Reign" season 4 premieres with "With Friends Like These" on Friday, Feb. 10, at 9 p.m. ET on The CW.