The usually conservative actress let it all hang out in a low cut lavender gown with a thin belt cinched around her waist and white peep toe pumps.
The film centers on Theodore Twombly (Joaquin Phoenix) a man who makes his living writing touching, personal letters for other people and ends up falling in love with "Samantha" (Scarlett Johansson), the voice behind a new, advanced operating system. Adams plays Twombly's friend and neighbor.
"Her" hits theaters on Nov. 20.
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