Catherine and Vincent are set to take on their own demons in the few remaining episodes of "Beauty and the Beast" season 4.

In episode 8 titled "Love is a Battlefield," the marriage of Cat and Vincent will be shaken by some things of the past that still haunt them. It can be recalled that when the two of them first met, Cat was only sixteen and Vincent was a beast.

Despite their differences, they still chose to get married and live a happy life together. However, the upcoming episode will put their marriage to test.

Episode 8 will see Vincent go undercover with a hot operative. However, Cat will find out that the lady is actually an assassin. While Vincent will have to play both sides, Cat will do her best to prove to the Department of Homeland Security (DHS) that she is still worthy of their trust.

The promo video for the episode shows Vincent having some intimate time with the lady assassin while Cat watches them from a surveillance camera. Although the clip does not reveal how the wife will react to what she saw, speculations suggest that Cat will still give Vincent her full trust knowing that he is not really a deliberate cheater.

In episode 7, Cat partnered with DHS to track her husband down but it turned out that she was actually up to something else. Vincent then sensed that Cat wanted to tell him something.

While the road has been bumpy for Cat and Vincent in the episodes leading up to the season finale, it looks like the two will still end up being together. In fact, in an interview with Zap2it, actress Kristin Kreuk said, "I hope the people who have struggled with the ups and downs of the main characters' relationship will feel very satisfied by the end."

"Beauty and the Beast" season 4, episode 8 airs on July 1, 9:00 P.M. on The CW.