Sean Penn is unrecognisable in first look at Watergate drama 'Gaslit' with Julia Roberts

Watch: Sean Penn unrecognisable in teaser for Gaslit

Sean Penn looks completely unrecognisable in first-look images for his new Watergate drama Gaslit, where he stars alongside Julia Roberts.

The 61-year-old Milk star is usually seen with chiselled, defined features, but as Attorney General John Mitchell he appears aged with jowls, a bald patch and white hair.

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He stars alongside Roberts, who viewers will also see in the images and first trailer as an older role than they might be used to as she plays Mitchell's wife Martha.

They are the key characters in forthcoming Starzplay series Gaslit, which takes a new angle on the Watergate scandal by looking at it through the lens of Martha who turned whistleblower on her own husband.

Martha was known as an outspoken socialite and was married to President Nixon's trusted adviser and best friend John Mitchell.

But despite her political affiliations, she was the first person to publicly sound the alarm on Nixon’s involvement in Watergate, causing both the Presidency and her personal life to unravel.

Temperamental and ruthless John is torn between his close friendship with Nixon and his love for his wife, finding himself forced to make an impossible choice.

Also seen in the first-look pictures are Downton Abbey star Dan Stevens as John Dean and GLOW's Betty Gilpin as Mo Dean.

Show creator Robbie Pickering describes the series as "the Watergate story you've never heard before" as it details the smear campaign against Martha, led in part by her own husband.

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He said: "The goal in making this project has always been to bring a real humanity to this subject, which yields a far richer and more relatable story than the standard male-driven political dramas about the period.

"I can’t wait for viewers to experience the extraordinary performances in this remarkable ensemble, led by Julia Roberts, brought to life in this thrilling, stranger-than-fiction tale of marriage, love, betrayal, and ultimately, hope."

Gaslit is based on the critically-acclaimed podcast Slow Burn and is due to launch on streaming service Starzplay on Sunday, 24 April.

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