The Heeler family stumbled upon Doreen’s yard sale while heading back home. Doreen’s goal was to raise enough money for her holiday to the reef. As they browsed the sale, Bluey, Bingo, and Muffin decided to play a game of Grannies. To include Muffin, who was new to the game, Bluey suggested she could be a grouchy granny, complete with a powerless granny mobile that Buggalugs would push.
As the kids played, Doreen struggled to negotiate prices with her customers. Chilli noticed that Doreen was being too kind and not making enough profit, selling a fancy vase for just two dollarbucks. Meanwhile, the kids’ game of Grannies continued, with Muffin playing the role of a grouchy granny and Buggalugs pushing her granny mobile. However, when Buggalugs expressed disinterest in buying the mobile for $300 dollarbucks, Muffin began to worry that she was being too grouchy. Bluey and Bingo couldn’t think of any other types of grannies, so Muffin ordered Buggalugs to take her home.
Just then, a real-life grouchy granny appeared, bumping into one of the tables and causing some items to break. She scolded Doreen and Chilli, refusing to pay for the damage. Later, when Muffin and Buggalugs returned to the yard sale, the old pug tried to buy Muffin’s scooter, but Muffin initially refused. The pug then offered Doreen $100 dollarbucks for the scooter, which Doreen reluctantly accepted. However, the pug then began to insult Bandit, calling him fat, and Chilli tried to intervene. Muffin, who was still playing the role of a grouchy granny, threw away the sign with the price of $300 dollarbucks and haggled with the pug. The pug eventually offered $1200 for the scooter, plus $2 for 18 lollies, raising enough money for Doreen’s trip. As a thank you, Doreen offered Muffin anything she wanted from the yard sale for free, and Muffin chose a tea towel to use as a super granny cape. The day ended with Bandit trying to buy some exercise equipment, and Doreen confidently haggled the price up to $50, impressing both Bandit and Chilli.