Dobbin the Pantomime Horse

Dobbin is a pantomime horse costume that happens to be alive, clip-clopping through the offices of Rentaghost with nobody quite explaining why. Two people share the suit, front and back, and Dobbin communicates the way any horse would — nuzzling, nodding, trotting about — while the human staff treat this as entirely unremarkable.

The joke is the deadpan: a talking, thinking horse suit accepted without comment by everyone around it, which is funnier the less anyone reacts. Asquith and Perrie manage real physical comedy from inside a costume with no face to act with, giving Dobbin more personality through posture and timing than most characters get from dialogue.