'Mad Men' Star January Jones Is Unrecognizable Without Her Blonde Bob

January Jones, whose name conjures images of the star in '50s fashion with a bright blonde bob hairstyle, left behind her signature hairdo for a new look that completely transformed her.

The Mad Men actress revealed that after years of rocking her signature hairstyle with slight variations to the cut, she decided to finally change things up, looking unrecognizable with new light brown hair styled in a soft messy bun.

Jones posted a photo of the updated look on her Instagram Stories, grinning at the camera in a cheeky yet relaxed outfit of socks, underwear, a red button-up cardigan and sunglasses.

It looks like Jones' new hairstyle might be for a movie she's working on called Altar, co-starring Kyle MacLachlan, David Krumholtz, Lily Collias and Hudson Behling.

The 46-year-old shared a recent update of what looked like a family portrait for the movie, with Jones standing with her arm around the actor who likely plays her son. The character has short soft brown hair with side-swept bangs.

While not much about the movie has been shared, Jones teased the horror film by sharing a quote from Ingmar Bergman's film Through a Glass Darkly that says, "The door opened. But the God that came out was a spider."

Bergman's 1961 film is about a woman suffering from schizophrenia who vacations on a remote island with her husband, father and brother shortly after being released from a hospital. Jones may be teasing that her new film Altar's story has similarities with that of Through a Glass Darkly.

Before that, Jones' last update for fans was in July, with the actress sharing some photos of herself in a red and white bikini and red hat as she enjoyed the bright sun and great weather.

At the time, Jones still had her light blonde hair, styled in a ponytail mostly hidden under the red baseball cap.

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