British theatre in the 1950s and 60s saw a revolution led by John Osborne and Harold Pinter. These playwrights challenged social norms, exploring themes of disillusionment and power dynamics through innovative styles and techniques. Osborne's "Angry Young Men" movement and Pinter's "comedy of menace" redefined post-war drama. Their works, featuring working-class characters and gritty settings, rejected genteel traditions and sparked controversy while leaving a lasting impact on modern theatre.