The Spottiswood Factory is making jigsaw puzzles. But Bertha the big machine is keeping some of the pieces to herself to make one of her own. Tracy designs a robot to help around the factory, a 'Talk Operated Machine', or Tom for short.
Bertha is making musical money boxes shaped like windmills. During lunch, Roy and Nell decide to test one of them, but can't find a way to get their coins out again. Meanwhile, Flo has lost her purse with all her money in it.
Spottiswood & Co is making Jack-In-The-Boxes, but the jacks keep escaping from their boxes because Bertha doesn't have enough glue to fasten them properly. When Panjid discovers there's a mouse running lose in the factory, Mr. Sprott is asked to develop a mouse trap.
Bertha is busy making humming tops. Mr. Willmake tasks Mr. Sprott to design an unusual toy for a competition. Mr. Duncan insists this toy is produced by the new Super Bumper & Presser machine instead of Bertha. But Ted decides to let Bertha have a go at it as well.
Tom is sent on an errant with a note for Panjid, but a magnet upsets his circuits, making him lose his way in the factory. Along the way he presents the note to a lot of people it wasn't meant for. Bertha refuses to work until Tom is found.
The C-246 lever that turns Bertha on and off is broken and keeps turning her off automatically. Nell hurts her finger, so Mrs. Tupp the tea lady gets out her nurses uniform and first aid kit. Maybe she can do something for broken Bertha as well?
While Mr. Willmake and Mr. Sprott are away, Mr. Duncan does a time and motion study and decides Bertha is moving too slowly. He orders her to be shut down and gives all the factory workers new tasks. But the workers don't take things lying down and form a protest.
Mr. Willmake receives an order to make 365 springs. Roy and T.O.M. have great difficulty transferring the whippy, springy steel that is to be used to make the springs from the dispatch dept. to Bertha.