Ep 14. Masquerade

In Smallville season 10 episode 14, titled "Masquerade," Clark and Lois attend a Costume Ball thrown by the town's medical association, honoring Martha Kent. As they enjoy the evening, Lois accidentally inhales an unknown powder and immediately begins hallucinating. Clark is quick to react and takes her outside to breathe fresh air. Meanwhile, Chloe and Oliver look into a suspicious suicide, which leads them to a conservative group who protest the medical association's work.

As Lois recovers, she starts to believe that Clark's secret identity is still out there and wonders if their relationship is truly meant to be. Clark assures her that he's been careful and discreet about his powers. But their conversation is cut short when they discover that someone has stolen Martha Kent's painting, which was on display at the ball. Clark and Lois soon realize that the thief is using the party as a cover and begin investigating.

Meanwhile, Chloe and Oliver discover that the suicide victim had connections to the conservative group leading them to believe there's more to the story than they previously thought. They discover that the group has been targeting people involved in the medical association and are willing to go to extreme lengths to stop their work.

Back at the party, it's revealed that the thief has taken the painting to uncover a family secret that Martha has been hiding. The secret involves a rare kryptonian crystal, which was passed down to her by a family member. The thief plans to use the crystal to expose Clark's secret identity to the world, while also using its powers to gain wealth and influence.

Clark and Lois team up to stop the thief and retrieve the painting before it's too late. In the process, they also learn the truth behind Martha's family secret and how it relates to Clark's past. The episode ends with Clark and Lois realizing the importance of honesty and trust in their relationship as they move forward.

Overall, "Masquerade" is an exciting episode that balances action, romance, and mystery. It explores the themes of family secrets, trust, and the consequences of one's actions. The episode also showcases the strong bond between Clark and Lois, as they work together to save the day.