Morc and Skelly have set a wager as to whose boat would win a sea race to the rocks and back and somehow Garth and Bev have gotten themselves mixed up in the challenge. But it's all at sea when the oars are lost overboard and the children take inspiration from jellyfish to find a way of propelling the boats back to shore.
It's the Ballybeg Winter Festival and Grandfather Lir asks Garth and Bev to find a way of displaying his grand collection of autumn leaves. The children accidentally discover that they can suspend them, frozen in ice. Lir is so pleased he sends them to meet Frank Epperson, who got his idea for the ice-lolly from a similar happy accident, when his lemonade froze on the porch overnight!
Grandfather Lir's brooch has broken and Garth and Bev offer to help mend it. But while Skelly the Blacksmith fixes it, Garth and Bev realize they have lost one of the precious stones. When they figure out that it must have got sucked into Skelly's bellows, Lir rewards them with a trip to see Hubert Cecil Booth, who used suction to solve the problem of household dirt with his vacuum cleaner.
When Elva's cat goes missing, Garth and Bev are charged with the task of finding her. As it gets dark, rather than making it more difficult to find the missing pet, Garth and Bev find that her reflective eyes makes her easier to spot! A bit like how Percy Shaw got his idea for keeping people safe with reflective road studs!
Morc and Skelly have gone fishing but without checking the weather forecast with Lir first. There's a storm coming and Garth and Bev have to send them a message to warn them. When they figure out that making a big pebble picture of a storm cloud on the beach really gets the message across they get to go and see John Logie Baird and the first TV broadcast!
Poor little Enda the Eagle, he's just learning to fly but keeps crashing into things because he doesn't know how to turn yet. Garth and Bev discover just which feathers he needs to move to turn in flight and as a treat; Lir sends them to meet Wilbur and Orville Wright whose great discovery used the same principles as inspiration for their aeroplane.
Garth and Bev are helping Elva make Milk Pudding, but her recipe tablet is so tiny, no one can read it. When they find out that things in water look bigger, they unlock the secret for magnifying the tiny writing on the tablet! Through the Time Spiral they visit Florentine inventor Salvino d'Armate, who figured out a way of using lenses to see things more clearly- The Eye Glasses.
There's a wedding in Ballybeg and with all the comings and goings, Dermot the Watchman is having a spot of bother keeping order at the crossroads. Garth and Bev discover that in nature, red means STOP and they travel through the Time Spiral to meet Gareth Morgan who used a similar idea when he invented the Traffic Lights!
Bertie the Boar has a terrible itch and has gone on a rampage through Ballybeg in an effort to scratch it! Meanwhile Garth and Bev have to clean Fiann's old cauldron and when they discover Bertie's bristly hair is the perfect thing for polishing old metal, Lir sends them to China to meet Lu Ping, who discovered another good use for pig bristles: cleaning teeth!
It's the day of the Great Ballybeg Race and Lir says Garth and Bev can compete this year. Trouble is the flags they've used to mark the route keep going astray and pretty soon, everyone is completely lost! When the children figure out that using a big muddy boulder to make a nice clear track, Lir sends them to visit Laszlo Biro in Budapest to see his invention; The Ballpoint Pen.
It's the day of the Ballybeg Annual Games and Garth and Bev are helping by marking out the squares for the 'Toss the Boulder' event. However everything they try seems to get squashed, eaten or blown away! Then they discover that charcoal is a great way of making marks, especially when you wrap it in a leaf to stop your hands getting messy.
Something's breaking all the pots in Hoyt's hut and the potter is convinced goblins are to blame. Goblins indeed! It's the vibrations from thunderclaps that are knocking Hoyt's pots over. Grandfather Lir send the children to meet Alexander Graham Bell, who figured out sound vibrations can be used for quite a different purpose; he's just invented the telephone.
Garth and Bev are collecting seeds for Grandfather Lir after Niall the Sheep naughtily ate all the ones in his garden. But Niall turns out to be a great help because they find that certain seeds stick to his wool and they can collect loads! Through the Time Spiral they discover that's a lot like how George de Mestral got the idea for his sticky clothing fastener.
It's that time of the year again when the wasps build their nests in Ballybeg and everyone is in a bit of a flap. The instructions for getting rid of them are in Lir's cave but no one can quite remember them correctly. Garth and Bev realise the wasps themselves hold the solution! Their nests are made of paper and the children can paint the instructions on it to carry it around.
Garth and Bev are helping Grandfather Lir to wash and dry his cloak after some very naughty animals messed it up! With a little help from Breck the Basket Maker they find out that the cloak flaps up in the air when it dries over his fire. And that's just like how Joseph and Etienne Montgolfier got the idea for their hot air balloon.
Garth and Bev need to help Hoyt the Potter carry his pots to market without breaking any. With a little help from some froggy friends, the children discover bouncy frog's cheeks are the perfect way to separate the pots and keep them safe. And that's a bit like how John Dunlop filled rubber tubes with air to keep people from rattling around on the bicycles!
Garth and Bev decide to build a duck house to keep their feathered friends safe from the fox. While they are at it they discover how the ducks keep dry in the rain and Grandfather Lir sends them on adventure to Victorian times to see how Charles Macintosh made a coat to help people to the same thing!