Tracy Vetter was on a temporary assignment with the 96th precinct but was permanently assigned as Nick's partner after the unexpected and tragic death of Schanke in a plane crash. She comes from a long line of cops and her father is none other than the commissioner of police. She had a hard start to her partnership after all Nick had just lost his partner and one of his best friends and his Captain in the same plane crash.

Tracy is one of the few who knows of the existance of vampires, she found out when she accidentally met one that should have died in the plane crash. When she told him to put his hands up he had actually lost a hand in the crash. His name was JD Valdez (who later turns out to be Javier Vachon under an alias) little did Tracy realize just how much this one vampire was going to change her life.

After Nick worked through his grief he and Tracy got along quite well and they worked well together as a team.
I think it made it a lot easier on him with his partner knowing there really are vampires and he didn't have to make up
so many excuses all the time. Tracy is very perky and at times can seem a bit yes like the typical blonde as well but
she's a good cop and a great partner. She and Vachon's relationship continued to grow and evolve and the two began to fall in love. I won't give away anymore than that you will have to watch the rest of the third season to find out the rest.