Natalia was a victim of spousal abuse by her husband Nick Townsend. Her association with the battered woman society helps the CSI team solve the murder of a woman who was killed by her ex-husband. Natalia is a Latina DNA analyst initially assigned only to work on unsolved or cold cases, though this is, until the end of season four, a cover for her.

At the end of season four it is revealed that Natalia is an FBI informant in the lab, assigned to help build a case against Horatio Caine and his team. However, when questioned by her co-workers, she claims to have only reported information that made the Miami Dade Crime Lab look good. It is eventually revealed that the negative information that was soiling the lab in fact came from another source, State Attorney Monica West (episode 425, "One of Our Own").

In episode 508, "Darkroom", CSI Ryan Wolfe finds a stash of photographed girls. Natalia discovers that one of the pictures is of her sister Anya. DNA from a crime scene reveals that Anya is indeed one of the women that the CSIs are looking for. It is also revealed that, in addition to Anya, Natalia has another sister named Cristine. At the end of the episode, Horatio manages to locate and rescue Anya, and the sisters are happily reunited. Eva LaRue's sister Nika was offered the role of Anya, Natalia's sister, but she declined. Instead she played a reporter. In fact, the episode was based on the real-life convicted serial killer William Richard Bradford; Nika LaRue was one of the women photographed by Bradford for his collection. She was no. 3 (out of 54 women) on the poster, created by the LAPD. Bradford would photograph women he met in bars under the guise that he would assist their modeling careers. ^[1]

In episode the"Internal Affairs", Nick Townsend is found murdered. All the evidence is pointing to Natalia as the killer. Horatio, the night-shift lab and Calleigh's ex-boyfriend Detective Jake Berkeley must find evidence to clear Natalia. Natalia admits to Berkeley that she was outside Nick's house. She was handcuffed by Jake at the beginning of the episode. Earlier on, Nick and Valera went on a lunch date. Valera ignored Natalia's warnings about Nick being dangerous so Natalia went there to watch over her. She sees Nick trying to force Valera into the bedroom and watches Valera push him and run out of the house. Thinking that she killed Nick, Valera tries to admit to Jake but he denies her confession. It is later discovered that another man murdered Nick over a pair of earrings that Nick had stolen from a crime scene (which linked the man's wife to said crime). At the end of the episode, Natalia leans on Horatio's shoulder and sobs quietly as they both look at a picture of Nick and Natalia in happier days, a reminder that Nick had not always been the abusive person he had become.

Relationships

Natalia and co-worker Eric Delko previously dated. Later on, they broke up because of a pregnancy scare (episode 415, "Skeletons). It was also subtly suggested that Natalia had slept with Eric to get information on the lab (episode 425, "One of Our Own"). Even if that was true, Eric remains protective of Natalia when her ex-husband Nick intrudes into crime scenes and harasses her. In episode 'Throwing Heat', Natalia always asks if Eric is alright and teases him. In the two part episode 'No Man's Land' and 'Man Down', when Eric is shot, Natalia is very worried and mentions to Detective Frank Tripp that Eric is all she can think about now.

CSI Level 1 Detective and co-worker Ryan Wolfe mentions to Eric that he wanted to ask Natalia out. When Eric and Natalia break up, Eric even gave money to Ryan to take Natalia out. However, in episode 413 "Silencer", Ryan walks into the lab to see Natalia and Eric laughing, close to each other. He calls out both of their names but they both ignore him. Frustrated, Ryan stalks out of the room.

In season 5, Natalia is now a CSI trainee. But to her grief and misery, Natalia discovers that her ex-husband is out of prison, and he serves her a restraining order. Nick begins working for a private crime-scene cleanup company. The situation is difficult as Natalia is forced to make terms with Nick so that he would drop the restraining order. In the episode "If Looks Could Kill", Natalia tells Nick to leave when he enters the CSI office. Nick says that the restraining order that she filed against him has expired. In episode 510, "Come as You Are", Natalia is shocked to find out that Nick had asked out lab technician Maxine Valera on a date and that she had accepted.