White Collar actress Marsha Thomason is sharing some of the secrets and motivations behind her character, FBI Agent Diana Barrigan.

Thomason revealed that for Barrigan, it is all about justice. She wants to nail the bad guys and save the innocent.

We all have a sense of right and wrong, but [Diana] really has a strong sense of that," Thomason said in an interview with Inside Blip. "She doesnt really deviate from it.

Diana also has a passion for solving crimes -- for no mystery is too great and no crime to elaborate. She is simply addicted to it all.

However, for Thomason, the challenges are entirely different. Being a British native, one of the biggest challenges is mastering both the technical language used on the show and saying it convincingly in an American accent.

Thomason admitted that during her first day on White Collar she had a terrible time enunciating the legal phrase exigent circumstances. It was only after several takes and a quip from co-star Tim DeKay, who plays Peter Burke, that reminded her that all she had to do was say the line -- it did not matter if she knew what it meant or not.

Thomason also said that while she enjoys all the action sequences, one of the trickier maneuvers is using the prop handcuffs. Because the handcuffs are not real, the prop's hooking mechanism foils her every time.

She is also not fond of Dianas wardrobe choice: suits, which pose a big problem in the intense humidity of New York where the show is filmed.

Despite those learning curves, Thomason is delighted to be playing such a strong and interesting character.

In a recent episode, In the Red, she gets to go undercover, which offers the fun aspect of playing a character within a character. She also enjoyed working on the episode Need to Know, which made her feel like Angelina Jolie with all the glamor and action.

I even told him I was going to shoot [Matt Bomer] in the shoulder," she said. "He didnt believe me and then I shot him in the shoulder!

Reflecting a bit about what she would like to learn about Diana, Thomason was reluctant to speculate too much, but did say: Id really like to see the relationship with Neal explored a little more. I work with Tim [DeKay] a heck of a lot on the show. We have a lot of scenes together. But Neal and Diana, its kind of a slow build, so Im really looking forward to seeing that story line develop.

Thomason is also very curious about Dianas girlfriend, and would love to explore that relationship a bit more too. Every time she broaches it with the writers, they reassure her that an episode with Christy is coming.

But Thomason is now starting to wonder if there even is a Christy.

Ive shot quite a bit of footage in Dianas house, but Christy is never there," she said. "Maybe Diana is just full of crap. Suppose she doesnt even have a girlfriend. Maybe Diana has never had a girlfriend and she just has a secret lonely life.

Thomason also let it slip that the audience will soon be getting an answer as to what is up with The Music Box. It is entirely too big of a white elephant between Peter and Neal to not be addressed relatively soon.

Finally, regarding Neals flirtatious pursuit of Diana, Thomason was amused at the idea that Neal might give up, saying: His ego is too big. Youve seen the way women swoon when he walks into a room ... its sport for him. Hes the guy that fakes art and steal,s and does all of that stuff for sport. Theres no way hes ever going to give up.

As for her recent opportunity to play opposite James Franco on General Hospital, Thomason said that it was both confusing and fun.

I didnt even know what I was doing," she explained. "They told me that I was going to be involved in espionage and that my character was going to be romantically involved with James, and none of those things happened. I was just confused the whole time.

White Collar airs Tuesdays at 9 p.m. ET on USA Network.