Almost half a century ago, the Prime Minister received an exceptionally unusual urgent memo with the highest security classification. He immediatley authorised a top secret SAS mission in NI. This has remained hidden until now – but is it the whole story?

PM authorised top secret use of SAS to thwart previously-unknown plot against NI’s top officer, file reveals – but is that the whole story?

Almost half a century ago, the Prime Minister received an exceptionally unusual and urgent memo with the highest security classification.