Bertha is making jixsaw puzzles, only to leave pieces back and making a picture of her own, so the workers have to re-do the puzzles. Meanwhile, Mr. Sprot's assistant Tracey designs a handy robot called TOM to help Mr. Wilmake and Miss. MacClakety paint their office.
Bertha is making Musical Windmill Money Boxes which plays music whenever money is put in. However, Roy discovers that when the money's in, you can't get it out! Everyone thinks that the Windmills are not designed properly. Meanwhile, Flo loses her purse with all her money in it...
Bertha is making Jack-in-the-boxes that fail to stay inside the box! When Panjit loads the remaining toys to the dispatch department, he sees holes in the boxes. Roy, asking for a tin of glue, rushes off to tell Mr. Duncan about the situation. It's soon discovered that a mouse is venturing around the factory, chewing on things and creeping inside Bertha! So Mr. Sprot has to design a mouse trap...
Bertha is making Spinning Tops that won't stop spinning! Meanwhile, Mr. Sprot is asked to make 'The Most Unusual Toy' by Mr. Wilmake. Mr. Duncan, the foreman, decides that the new Super Bumper Compresser Machine should do the job, which upsets Bertha...
Tom the robot causes confusion when a magnet upsets his circuitry.
Why are the plastic bears made by Bertha getting bigger and bigger?
Bertha has a faulty lever, but Mrs Tupp comes to the rescue.
Mr Duncan does a time and motion study whilst Bertha makes garden gnomes and a special gnome for Panjid.
Bertha has to make 365 new springs, but Tom and Roy have trouble with the twanging steel.
Bertha is making Jumping Kangaroos. When Ted accidently sets one off, the others in the boxes jump around the factory! When the batteries run down, it's closing time, so Ted stops Bertha and they go home. That night, however, TOM spots burglars enter the factory and into Mr. Wilmake's safe...
Bertha is busy making cuckoo clocks when Miss McClackerty discovers that it's time for a birthday celebration.
Bertha gets so cold that the beach balls she makes look like snowballs.
Mrs Tupp is cross about a new machine that is delivered, but Tom thinks that it is a new friend.