The Twirlywoos are in a back garden where a children's birthday party is going on. There is a machine which makes bubbles and the Twirlywoos watch as the children have fun running around and popping them all. The kids go back inside and the Twirlywoos come out to investigate. Great BigHoo finds the switch that turns the bubble machine on, and Chickedy, Chick and Toodloo race around popping all the bubbles. Great BigHoo finds a dial on the side of the machine. He turns it and the bubbles start to get bigger. The big bubbles make bigger pops and the others are delighted. Great BigHoo turns the dial further and further, making the bubbles bigger still, until, not knowing his own strength, he pulls the dial right off the machine! It starts to go into overdrive, producing an enormous bubble which fills the whole garden. The Hooter honks, and the Twirlywoos leave, just as the children run outside to see the giant bubble burst with an enormous POP! Back at the Boat, the Twirlywoos are having tea. Meanwhile, Peekaboo has got the hiccups. Each time he hiccups he blows a bubble, which floats over to the table where the Twirlywoos are just about to drink their tea. They all raise their cups just as the bubble bursts with a loud POP and the Twirlywoos all jump in surprise! They recover their composure and get ready to take another sip when another bubble floats in and pops, and they jump again. The last bubble is an extra big one, and the pop is so loud that the Twirlywoos jump even higher and the tea splashes right up out of their cups! As the tea falls down, they manage to catch it in their cups and drink it all.