Trouble is brewing on “Reign”! Episode 18 aired on April 17, exposing some serious marriage problems for our favorite characters.

“No Exit” kicked off with Bash gifting Kenna with a family heirloom ring and promising to try in their relationship. But unfortunately for Kenna, she has the mad king following her around.

It’s the day of Lola’s wedding, and while the day should be joyous, everyone is worried about Henry – especially since the Cardinal is in town for the week to meet with him. Catherine is worried that the Cardinal will find out that Henry is married, but Mary comes up with an idea – convince the Cardinal to meet with her and Francis instead. And thanks to a little bit of flirting, her plan works.

However an unexpected kink gets thrown into their plan – Mary’s half brother, James. Arriving at the castle, James tells Mary that Marie de Guise is in trouble and that she must return to Scotland.

Mary immediately agrees, but Francis doesn’t want her to go – especially with the Cardinal in town. With France at risk, Francis tells Mary that they need to wait and can send some French diplomats for the time being. Needless to say, that becomes an issue for the newlyweds.

“My country and I are one in the same,” she argues with Francis. “Forget that and you’ve forgotten who I am.”

Mary and Francis aren’t the only ones with a struggling relationship. Lola’s become uncertain about Lord Julien after he becomes focused on obtaining her dowry before going on their honeymoon tour. And she gets outright suspicious of him when she discovers that one of the gems on the necklace he gave her is fake. Lola confides in Grier, who tells her that she’s thinking too much into it. But is she? With two dead wives behind him, it’s possible that Lord Julien is a bluebeard (male version of a black widow).

In other parts of the castle, Nostradamus and Olivia decided to take their relationship to the next step. But after a romp in the sack, Nostradamus has a vision of Olivia laying dead with a handful of other bodies. Afraid for his new love, Nostradamus tells Queen Catherine that he’s leaving to start a new life with Olivia. But the Queen doesn’t accept his resignation – leading Nostradamus to threaten to not reveal any more of his visions to her. The Queen finally agrees to let him go … but not before telling him to be careful of venom. When Olivia almost gets bit by a snake, Nostradamus forces her to leave – without him.

Meanwhile Penelope is spewing her own venom in the castle. Becoming jealous of Henry’s fascination with Kenna, she makes Kenna give up the ring that Bash gave her. Bash is angry with his father, and Henry tries to make peace by making Catherine give Kenna a ring right off her fingers.

When Henry walks away, Kenna tries to hand it back to Catherine. But Catherine surprises her by telling her to keep it as a token of her sympathy – and then also asks for her help.

Catherine wants to get rid of Penelope but can’t poison her because Henry will know it was her. Kenna initially refuses, but changes her mind when Catherine offers her an estate for her and Bash to live in peace.

So, what is Catherine’s plan? Sex!

Fortunately it doesn’t involve Kenna having sex with Henry, but it does involve Kenna giving Penelope some sex tips. Since Penelope is bent on keeping Henry satisfied, she listens to Kenna – who suggests she tries “The Standing Cross” on Henry.

And Penelope does just that. But just as Queen Catherine planned, Penelope’s sex act backfired. Penelope used rope to tie Henry up like a cross – something that Henry didn’t enjoy because he feared he was insulting God. However Penelope doesn’t listen to him when he asks for her to take him down. Instead she tells him that Kenna said he would beg.

Before things go any further, Catherine barged into the room with a fake Bishop. The Fake Bishop acts appalled by seeing this “mockery,” and convinces Henry to kick Penelope out. Despite Penelope’s pleas, Henry listens to the Bishop. Turning to Catherine, he collapses into her, telling her that he’s lost and need’s God’s support. And Catherine promises to help. But Henry might be beyond help. Left alone, the ghost of a man holding a racket appears before him – leading him to yell, “Leave me alone. Get out. Please go.”

Francis realizes that he must help Mary too. After a talk with Bash, Francis returns to Mary and agrees to leave as soon as possible for Scotland. Mary’s overjoyed, but her brother isn’t. James wanted Mary to go alone, and shortly after manages to convince her to leave early without Francis.

But Francis discovers that something is wrong when he finds James’ footman carrying English gold. The footman reveals that he was paid by the English to murder Mary because they want James to be king. Francis tells Mary what happened, but Mary doesn’t believe her brother is involved. Bent on helping Scotland, she warns Francis that she’s leaving that moment – with or without him. Francis says okay … and then orders his guards to detain Mary.

Episode 18 concluded with Francis locking Mary in a tower – and Mary threatening to never forgive him if something happens to Scotland.

What did you think of episode 18 of “Reign”? Let us know in the comments section.