'Suits' Season 3 Spoilers: Harvey and Donna's Mysterious Past Revealed

As the summer slowly winds down, so does the season's biggest television series. USA Network's "Suits" is approaching its season finale with a handful of loose ends that have yet to be resolved. With only five episodes remaining, they promise to be the most exciting yet.

In a recent interview with The Hollywood Reporter, Sarah Rafferty, who plays Donna on the show, opened about her character's complicated relationship with Harvey. In this week's episode, which airs tomorrow night, the actress hinted that fans will "get a chance to understand why they have the character traits that they do and why their relationship is the way it is."

In the episode, Harvey will respond the news of Donna's late-night rendezvous with Stephen, who many call the British version of Harvey. How will the unpredictable Harvey react? Fans will have to wait and see, but Rafferty offers a quick glimpse at their future.

"I think both Harvey and Donna might be surprised by what it brings up for them, the issues in their relationship that they need to address and ultimately that they are incredibly loyal to each other and have a really solid foundation," Rafferty said. "And we learn more about that in the flashback episode, which is perfectly placed as the sixth episode."

The actress also commented on how the remaining episodes will tie up the ample loose ends that remain in the third season. In terms of Harvey and Donna's relationship in particular, "it should be dragged out, our knowledge of them, of why they are the way they are, right? You should not be able to figure it out for a long time. Also, I think they're two complicated people who don't know themselves."

Finally, she teased that the upcoming flashback episode will help fill in the gaps of their mysterious relationship. "I'm eager to see the flashback. I'm eager to see how that weaves into the season. I thought the flashback was so brilliantly placed in season two -- it was just the perfect moment to go back in time, and I think it will be interesting to see them go back even further in time. The way it juxtaposes the present to the past is intriguing. Gabriel and I had fun playing 10 years in the past for Harvey and Donna. It was a good time."

Tune in for an exciting and revealing episode of "Suits" Tuesday night, August 20, on USA Network.