Brad Garrett Stirs Up Trouble as Charlie’s Dad on ‘Manhattan’ (VIDEO)

Fans of WGN America’s Manhattan know little of wunderkind physicist Charlie Isaac’s (Ashley Zukerman) childhood other than that his estranged father’s in prison for illegal gambling. Well, it seems dear old dad’s been released. In tonight’s episode, Eli Isaacs (guest star Brad Garrett) turns up near Los Alamos “on a very personal mission,” says executive producer Sam Shaw. He wants to see his son, who happens to be one of the most valuable guys in the US of A for one reason: he’s trying create the world’s first atomic bomb.

It’s bound to be a prickly visit. Charlie’s memories include accompanying his dad to card games, where he’d be left to fall asleep on a sofa while his father “lost his shirt,” notes Shaw. For better or worse, “Eli sheds some light on who Charlie was before he crash landed on this desert island of Los Alamos and what past Charlie turned his back on to remake himself.”

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Meeting her father-in-law for the first time, “is an education for Charlie’s wife, Abby (Rachel Brosnahan), about who her husband is,” the producer adds, ”and deepen the understanding of this man that she’s (sometimes unhappily) married to. Charlie is someone who’s acquainted with violence and ugliness in an intimate way as opposed to the other scientists who are inventing this weapon of massive violence.”

Manhattan - Brad Garrett

As for Eli, “He’s much more honest about his own failing as a father than we expect him to be. We knew that Eli was a looming presence for Charlie,“ says Shaw, “and Brad Garrett, besides being an incredible comic actor is also an incredibly deep and soulful actor. There’s such a sense of history and pain and complexity in him. Seeing Brad Garrett and Rachel Bresnahan go toe-to-toe is a highpoint of the season to me. Plus, uncannily, he looks a bit like Ash Zuckerman.”

Watch an exclusive first look clip of Eli as he makes himself known on tonight’s episode. Security is taking some interest in this guy who’s trying to contact the top-secret site where his son’s a top dog.

Manhattan, Tuesdays, 9/8c, WGN America