The episode opens with a rather fit looking Harold "working out"

Albert arrives and conducts his usual review of the days totting to find that Harold has purchased a job lot of torture instruments including a straightjacket. Informing Harold that its "the first of the month" and he wants him to help him check his Premium Bond numbers.

First point to note is that the still from the cover of the BBC Series 3 box is from this scene although Harold is wearing a vest rather than the t-shirt he wears in the show.

Harold's ridicule at Albert's hopes of winning , soon turns to excitement as they discover that the old man has won £1000. Excitement turns to dismay as we discover that the winnings belong solely to Albert after Harold had sold his share of the bonds to Albert so that he could join the tennis club.

Now shocked Harold is forced to act quickly to save his father from losing all his winnings. he has to prove that Madge is just after the money. Seeing his chance in the kitchen he gags then wraps Albert in the straight jacket. Then after covering Albert's mouth in shaving foam proceeds to create a scene whereby Madge runs to the kitchen.

Second point to note is the great bit of improvisation at 20:48 where Harold opens the door and promptly pulls the door handle off to then subtly place the handle in his pocket. No retakes here!

Harold now pretends that the old man has gone mad and stolen the money as he always does. Horrified at the mention of the police being called Madge confesses the whole thing was a scam gives the ring back and saying "He was the fifth one this year" before making a quick escape.