Yes, Prime Minister (1986)

Following a series of circumstances involving the Eurosausage, the Home Secretary drink driving and the Chancellor's dalliances with a shady lady from Argentina, Minister for Administrative Affairs Jim Hacker finds himself elevated to Number 10 Downing Street without being quite sure how he got there. But life as Prime Minister is no easier than being a Minister; Hacker still finds his every move challenged by the Civil Service as represented by his new Cabinet Secretary, the ever-wily and manipulative Sir Humphrey Appleby, who is as equally determined that nothing should change as Hacker is that changes should be made. Wandering nervously between them is Bernard Wooley, Hacker's private secretary, who continues juggling his responsibilities to his political master with his loyalties to his Civil Service colleagues...