John Hurt was in it, but Ian McKellen (with shaved head to try and look like the middle aged original) played John Profumo, the Secretary of State for War (and hence a potential target for Soviet blackmail) who was involved with the 19 year old Keeler. She was also shagging the Naval Attache (read KGB spy) at the Soviet embassy. Quaint by today’s standards, but probably the sort of thing the Democrats are dreaming about for anyone in Trump’s circle.
Guess that's why they call it "acting".