St. Denis Medical is preparing for an explosive season finale - and that starts with a shocking kiss. During the Monday, March 30, penultimate episode of the hit NBC sitcom, Matt (Mekki Leeper) and Serena (Kahyun Kim) took their relationship to the next level, which they exclusively told Us Weekly came with some "pressure" after offscreen interest from viewers. "I was so nervous. Us, the writers and everybody that works on the show has been very careful to make this a believable and satisfying arc," Leeper and Kim said about working to make a fictional "relationship they root for" on the show.