Agent Carter's Howard Stark has a Captain America-sized secret.

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The famed inventor is currently running from the SSR, and he will infuriate one of his only allies in "The Blitzkrieg Button."

Stark (Dominic Cooper) and Jarvis (James D'Arcy) are keeping a major secret from Peggy (Hayley Atwell), and Carter will not be pleased when she finds out the duo are trying to pull the wool over her eyes. The agent may be even less forgiving when she realizes Stark's deception is tied to the Star-Spangled Avenger.

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"[Howard Stark's] return comes right on the heels of [Peggy] learning that Howard and Jarvis lied to her...and their lie has a little something to do with her long lost love, Captain America," E! teased. "Expect Peggy to shut Howard down during their knock-down, drag out argument in the best possible way--her scathing and honest words."

"The Blitzkrieg Button" will also feature an appearance by Stan Lee.

Find out more when Agent Carter airs Tuesdays at 9 p.m. ET on ABC. The Marvel series will take a break on Jan. 20 for the State of the Union, but will return on Jan. 27. Click the video below to see a preview for the series' next episode.

Tags: Agent Carter television ABC Marvel