We may not know who Gabriel Maddox (Rome Flynn) is yet, but at least we know he'll play a major role in How to Get Away with Murder Season 5.

Deadline reports that Flynn, who briefly guest starred in the Season 4 finale, has officially been hired as a series regular for Season 5. In his one and only scene so far, Gabriel showed up to Middleton College to sign up for law school on the same day as Frank (Charlie Weber). Upon seeing him, Frank immediately made a call saying, "Looks like the good times didn't last too long. Her kid's here."

Ultimately, that's not a whole lot to go on, which showrunner Pete Nowalk says is on purpose.

"He said, 'Her kid's here.' We really like to play with the pronouns here," Nowalk explains. "Obviously, Gabriel has a mother, and Frank knows of that mother or knows the mother. So that is a huge mystery, and we're going to be giving hints about it all next season."

How to Get Away with Murder Finale: Who Is Gabriel Maddox?

Frankly, we're just as interested to find out who Frank made the call to as we are to figure out who this kid is.

The popular theory is that he could be Bonnie's (Liza Weil) long lost son from when she was younger. Though we knew Bonnie had been sexually assaulted multiple times when she was younger, Season 4 revealed that one of her assaults resulted in a pregnancy. During the birth, Bonnie passed out, and when she woke up her father told her the baby had died. However, Denver's (Benito Martinez) files indicate that Bonnie's child could still be alive, and it's a pretty big coincidence that Maddox turned up right as that tidbit got revealed.

As for when that mystery will ultimately unravel, Nowalk would only tease that it wouldn't be too long, but we should expect to get to know this character as a person a little bit before the show reveals his origins.

Who's son do you think he is?

How to Get Away with Murder will return Thursdays at 10/9c this fall on ABC.