Having given evidence during the Leveson inquiry in London earlier that day, Emilio PucciLBD, complete with lace sleeves and asymmetric tasselled skirt.
Dishevelled locks, a matching leather clutch and classic Louboutin courts provided the finishing touches.
Très chic, non?
Let us know what you think of Sienna's top-to-toe black in a comment below.
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