It is 8 o'clock at night and it is time for Pingu and Pinga to get ready for bed. They come inside from playing with snowballs and go to the bathroom to brush their beaks. Whilst squeezing some beakpaste for Pinga, Pingu squirts it on the mirror and makes a fiendish shape from the pattern. Mum storms in and tells them to stop messing about and go to the toilet.
At last, the two young penguins are in bed and drinking their milk. Pingu tries to blow bubbles in his milk, but Mum scowls at him and he gulps it down straight away. Mum kisses them good night puts out the light. Pinga is just dozing off when in the light of her night light, she sees the shadow of a monster on the wall and is very scared indeed. Seeing Pinga trembling with fear, Pingu turns over in bed and is also scared by the shadow, but then realises that it was being cast by a mask and some other stuff in a basket. Pingu makes a shadow of a bird in flight with his wings and Pinga comes over to sit on Pingu's bed to watch. Pingu then makes the shadow of a fish, a duck and a dog. Pinga claps from her enjoyment and Pingu then makes the shadow of an octopus, a bear and a robot. Pinga then wants Pingu to do Robby, but is not very impressed by his attempt and does a better one herself.
Now Pingu and Pinga are having a shadow-off: Pingu makes the shadow of a toy sailing boat and Pinga makes a comeback with a schooner. Pingu is amazed and after some thought, he makes a shadow of their dad and mimics him, which Pinga applauds at. Then the real Dad comes in starts telling them sternly to got to sleep, but Pingu, still looking at the wall thinks that Pinga has made a lifelike shadow of him and is impersonating him accurately and claps wildly. Then he realises that Pinga is not doing anything. He looks slowly round to see Dad glaring at him. He tries to tell them to go to bed, but he is so tired that he falls asleep himself when Mum come in later, she finds him sleeping on Pingu's bed with Pingu and Pinga under his wings. She chuckles and puts Pinga's blanket over them all three of them and lets them all sleep there for the rest of the night.
- The mask is the same one that Grandpa wore in Pingu's Moon Adventure.