Agatha All Along: Who Plays Billy Kaplan’s Parents (& Where Have You Seen Them Before)?

Warning: The following article contains spoilers for Agatha All Along Episode 6, “Familiar by Thy Side.”

Agatha All Along‘s latest entry, “Familiar by Thy Side,” introduces two key supporting characters: William Kaplan’s mom and dad, Rebecca and Jeff. So, who plays Billy’s parents in Agatha All Along, and what other roles are they known for?

Who Plays Billy Kaplan’s Parents in Agatha All Along Episode 6?

Maria Dizzia and Paul Adelstein portray Rebecca and Jeff Kaplan, respectively, in Agatha All Along Episode 6, “Familiar by Thy Side.” While the pair have a relatively small amount of screentime, they’re nevertheless crucial to the episode’s narrative. Aside from being William Kaplan’s folks, they’re also part of the car accident that results in Billy Maximoff’s soul ending up in William’s body. Rebecca and Jeff are the first people William/Billy uses his magical mind reading powers on, too.

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Funnily enough, Dizzia and Adelstein’s casting was one of several behind-the-scenes clues pointing to Agatha All Along‘s big Billy/William twist prior the show’s release. A press briefing circulated in September 2024 listed Dizzia and Adelstein as Rebecca and Jeff, respectively, confirming the Kaplans’ inclusion in Agatha All Along. As such, many fans were quick to conclude that Joe Locke’s “Teen” was secretly the reborn Billy.

What Other Roles Are Maria Dizzia and Paul Adelstein Known For?

So, that’s who plays Rebecca and Jeff Kaplan in Agatha All Along. But where do you know them both from? There are loads of possibilities; Maria Dizzia and Paul Adelstein are regulars on the acting scene. That said, Dizzia is probably best known for her turn as Polly Harper in Netflix’s Orange Is the New Black. She also had a recurring role in another high-profile Netflix series, 13 Reasons Why, and cropped up in a supporting role in 2013 Tom Hanks vehicle Captain Phillips.

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Meanwhile, Adelstein was major player in Prison Break, starring as Paul Kellerman in 48 installments of the Fox crime drama. He amassed an even more impressive 111-episode run as a series regular on ABC’s Grey’s Anatomy spinoff Private Practice, as well. His film credits include Memoirs of a Geisha, Be Cool, and The Menu.

Agatha All Along is currently streaming on Disney+, with new episodes dropping Wednesdays.