I'm trying to remember the details but I feel sure I saw her play Ophelia at Nottingham rep - sometime in the late 1960's/early 70's.

Apparently she played the role in a film.

"Gabriel Rieger

Few Shakespearean performances have proven as polarizing as Marianne Faithfull’s Ophelia in Tony Richardson?s 1969 film of Hamlet. In a January 12, 1970 review of the film, Time Magazine declared her performance “remarkably affecting… ethereal, vulnerable, and in some strange way purer than the infancy of truth.” Other critics have been less effusive. David Bevington, reviewing the film in Shakespeare: Stage, Script, Screen writes that Richardson?s “most controversial choice involves Ophelia, acted (poorly) by rock singer Marianne Faithfull, who looks like a sixties flower child.” Dianne Hunter, in an article for the online journal PsyArt, writes that Faithfull?s performance evokes other icons such as Twiggy and Mary Travers in “the 1960s … ideal of femininity,” while Robert Shaugnessy, writing in Henderson?s A Concise Companion to Shakespeare on Screen, dismisses Faithfull?s performance as “blank and understated for the first part of the film … a vacuous sex object” who “degenerates into a perverted flower child, an acid casualty serving as a focus for Hamlet?s (and perhaps the film?s) prevailing misogyny” (73).

In her 1994 book Faithfull: An Autobiography, the singer recounts her experience of playing the role. Faithfull writes:

For years I had been babbling about death in interviews. That was playacting. There came a time, however, that it stopped being a performance. The combined effect of playing Ophelia and doing heroin induced a morbid frame of mind – to say the least – and I began contemplating drowning myself in the Thames. "

As for her achievements. I wish I'd accomplished as much.