Helen Mirren hasn't ever been shy about doing totally nude scenes. If you want to see her looking fantastic at the beginning of her career watch Age of Consent with James Mason (it shows up on IFC/Sundance occasionally). She cavorts topless/naked on an Australian beach many times and she is probably 22 or 23 y/o.
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"I'm a minor character in my own story", Steve Coogan as Tony Wilson in 24 Hour Party People