After she's seemingly stood up by Vincent, Cat wonders if it's because he saw her kissing Evan at her birthday. Actually, Vincent mysteriously blacked out on his way to meet Cat, and is now searching for answers. Cat's case pulls her into the sophisticated world of the SoHo art scene. When Vincent finds Cat all dressed up to go to a gallery opening -- with Evan -- he has to admit that his feelings for her are growing deeper. All the while Evan makes his affections for Cat known, leaving Cat torn between the two very different suitors.

JT suspects that Catherine is the trigger of Vincent’s blackouts, so to disprove this theory, Vincent allows JT to inject him with endorphins and sedatives that force him into a fugue state. In flashback, Vincent recalls his time in Afghanistan when he received his first super soldier shot, and remembers who injected him with the DNA altering substance. He also recollects how the other soldiers experienced unpredictable side effects, including fugue states, and is relieved to know that Cat isn’t causing his blackouts. Vincent shares his memory about Murifield with Cat, who experiences some recollections of her own. Then, as Cat and Tess investigate the attempted murder of a teen pop star, Evan suspects that Cat is deliberately protecting the vigilante who saved him in the subway.

When Catherine’s dad gets remarried, the bride-to-be and her bridesmaids try to find the daughter-of-the-groom a date for the wedding. Uncomfortable with being set up, Cat reluctantly admits that she’s seeing somebody and confides to Vincent that she wishes he could be her date. At the wedding reception, Cat learns about a research grant that Evan received to study the mutant DNA cells found at local crime scenes. When she tells Vincent about Evan’s theory of how the cells are changing to become more animal-like and less human, she encounters an unexpected detour that could change the course of their relationship. Meanwhile, Tess and Joe cross the line romantically despite the fact that Joe is a married man.

On the anniversary of her mother's death, Cat asks Gabe to attend her family's annual remembrance of Vanessa, which makes Vincent incredibly jealous. Cat learns some information that makes her think her mom might still be alive and when a sniper shoots the mayor at a public event, Vincent finds evidence that links Gabe to the sniper.

When secrets about Cat’s family are revealed, it will change everything Cat knew about her past. Vincent finds himself staring his demise in the face; while Gabe takes drastic measures get some answers.