While the Beeb's spy show may not be an accurate reflection of life in MI5, the wealth of white-knuckle storylines that routinely mirror today's news headlines ensures proceedings are (relatively) grounded and, five years in, as vigorously enjoyable
as ever.
This years threats (Islamic/eco/religious terrorists, rogue spies, government coup détats) are juxtaposed against Adam Carters (Rupert Penry-Jones) compelling slide towards a breakdown, while the arrival of Hermione Norris icy Ros Myers provides
a highly welcome frisson to The Grid and Peter Firth continues to be the steely core as unflappable vet Harry Pearce.