Claude and Leith first meet in Tempting Fate. Catherine informs Leith that he has promoted to a personal bodyguard for Princess Claude. He tries to make excuses for why he might not be suitable but Catherine ignores them. She wants him to be at her side and keep her occupied at all times. When Claude began to complain about her mother assigning her a bodyguard, she saw Leith and suddenly approved.
In Reversal of Fortune, Leith tries to out of his duties of looking after Claude as he needs to take care of an errand in town, but Catherine refuses and tells him to take Claude with him. Catherine does not want Claude to know of Francis' collapse and Leith understands the situation, agreeing to take Claude elsewhere. When arriving at in town, Leith tells Claude to stay in the carriage. After he leaves, Claude asks the driver to where the most unsavory place in town. When Leith returns to the carriage, he finds Claude not there and the driver tells him that she went to Greer's brothel. He goes to get her and takes her back to the castle. Kenna accidently lets it slip about Francis' illness which Claude knew nothing about. Claude becomes irritated that Leith didn't tell her but thinks she could turn over a new leaf with him even though so many ladies of from the brothel know him. He confesses that it’s because he and their madam are together.
In Fugitive, Claude is badgering Leith to take her to see her lover in town. As Leith refuses, she tries to bribe him into looking the other way so she can do whatever she wants. He makes an excuse saying that he’s got an errand for the cardinal. However, she catches him trying to steal the jeweled dagger. She lets him know that she can turn him in and see him hanged or she can keep quiet and he can escort her wherever she likes and cover for her with her mother. In town, Claude reunites with her lover while Leith waits outside. Back at the castle, Claude starts acting out and demands that Leith ends his relationship with Greer. He refuses to do so and tells her why he tried to steal the dagger. He sees that she got her heart broken by her lover and explains to her what love truly is. He hopes one day that she will find her true love but doesn't drive them away with her temper. She holds out her diamond earring and tells him to take care of his problem so that she never has to hear about it again. He kisses her on the head and thanks her.
During The Siege, Leith protects Claude from the dangers that come to the castle. At the beginning of the episode, Claude sees Leith and Greer together and becomes curious their relationship but Leith believes there's nothing to tell as they are over.
When Francis decides that everyone should be sent to different secret locations as Condé is planning to start a war, Leith is to escort Claude to her location however, they are ambushed by English soldiers. Leith orders Claude to run and hide while he fights off the soldiers. She hides in the old secret passages and waits for Leith to come. Later, he finally shows up and she's thankful that he saved her. She apologizes for being difficult and prying into his personal life. He tells things that Greer refused his proposal and she tells him to cut Greer a break. Claude admires Greer’s fierce independent streak but Claude wouldn’t turn down having someone like him at her side always. Claude then sees someone behind Leith and screams. He goes to investigate but doesn't find anyone. He believes that she may have been seeing things but she’s convinced she saw a demon.
In Burn, Claude informs Leith about the creature she had seen in the secret passages was recently accused of attacking one of the chamber maids. Leith still believes what she saw in the passageways was just her imagination. However, Claude believes that Delphine may be a shape-shifting creature.