The Oscar winner will have "a lot of conflict" on screen with Viola Davis
Credit: Mitch Haaseth/ABC

Marcia Gay Harden is no stranger to playing strong women. The Oscar winner has shared the screen with plenty of talented actresses, but going toe-to-toe with SAG winner Viola Davis certainly kept Harden guessing.

“You have to be on your game,” she tells PEOPLE of pairing with the How to Get Away with Murder star, 49. “You have to be ready to go right away. If she’s the quarterback, you’ve got to be ready to receive and then do a little dance of your own to make it exciting.”

In fact, guessing makes up pretty much the whole playbook on the Murder set, according to Harden, 55. “No one know what’s going on, including the actor. You don’t know much about your character or, more importantly, what’s coming in the future,” she says of the ABC whodunnit’s super secretive vibe. “You land on your feet, and you start running right away – and you want to be sure you’re running in the right direction. If you want to score a touchdown, you want to be running in the right direction!”

Harden extends her Super Bowl-ready metaphor to her first few days of shooting, saying they were more “running in circles.”

Quite the opposite is true for her character, Hannah, whose exact relations to the central mystery is being kept closely under wraps. Harden, however, will say that, “Hannah is sort of honest to a fault, whereas Annalise is very comfortable with secrets, and that galls my character.”

Harden also teases the characters’ “family history”: “There is a teeter-totter between the two ladies historically where they’re very different personalities.”

For all their differences, they do have a few things common. “We’re both fueled by a little bit of damage,” says Harden. “Both women have an imperiousness and a pride that allow for a lot of conflict.”

Harden’s first of a three episode arc debuts when How to Get Away with Murder returns from its winter hiatus Thursday at 10 p.m. ET on ABC.

How You Would Get Away with Murder