Animated adventures of builder Bob and his friends - Travis the tractor, Scoop the bulldozer, Lofty the crane and Dizzy the cement mixer. Bob finds a hibernating hedgehog - and it ends up in Roley's care. Scruffty leaps out of Travis's trailer and chases Pilchard around the yard. Terrified that they will wake the hedgehog, Roley calls Farmer Pickles back to sort things out. Bob and Wendy return to find the Machines singing a lullaby to the snoozing hedgehog.