Only Fools and Horses - Season 0 Episode 38 Russell Harty Sketch Cushty!
Overview: A combination of script and ad-lib form a short sketch on the 1983 Christmas Special of Russell Harty's show, Harty. At one point David Jason indirectly involves a member of the audience, and even after the sketch is thought to have ended and Russell Harty thanks the actors, they remain in character, talking to Harty like so, who in turn speaks to them as their characters.