Conversation so far:
Where did Helen attend school?
CANNOTANSWER.
What significant events occurred during her early years?
As a result of her work for the National Youth Theatre, Mirren was invited to join the Royal Shakespeare Company (RSC).
What plays did she appear in?
she played Castiza in Trevor Nunn's 1966 staging of The Revenger's Tragedy, Diana in All's Well That Ends Well (1967), Cressida in Troilus and Cressida (1968).
Did she win any awards?
CANNOTANSWER.

Question: What did she do after her time with the Royal Shakespeare Company?
Self-contained rewrite: What did Mirren do after her time with the Royal Shakespeare Company?