Sir Arnold Robinson

Sir Arnold Robinson is the Cabinet Secretary, the most senior civil servant in Whitehall, gliding above the departmental trench warfare between Jim Hacker and Sir Humphrey. He appears when things need calming, arbitrating, or quietly steering, dispensing weary wisdom about how government actually works with the unhurried confidence of a man who has outlasted several governments already.

Nettleton plays him as the grown-up in the room, amused rather than alarmed by the scheming below him, which lets the show widen its satire from department to system. His dry asides carry the sense of a man who finds the whole business of governing faintly ridiculous but never lets that stop it running smoothly.