Samantha Morton

Warner Bros.

The Whisperers have found their leader in Samantha Morton.

"The Walking Dead" has cast the "Fantastic Beasts and Where to Find Them" actress to play Alpha, one of the most iconic villains in Robert Kirkman's comic series. Kirkman announced the news at the show's Comic-Con panel today.

Fans have been speculating for months about whether the Whisperers would make an appearance in Season 9, which will debut Oct. 7 and be the final season for star Andrew Lincoln.

It seemed very likely the group would be introduced soon, as that aligns with the timeline in the comic books. The Whisperers wear skin suits made from human flesh in order to blend in with zombies. And they believe that the undead epidemic was the natural next step in evolution.

Morton's Alpha is their ruthless leader, who is bald beneath her zombie mask. In the comics, her daughter Lydia becomes a love interest for Carl Grimes, but that will have to change since Chandler Riggs exited the show last season.

In the comics, Alpha quickly finds herself at odds with Rick (Lincoln) and makes her stamp by killing several members of his faction. With Lincoln confirming his exit this season, could his death be on Alpha's hands?