Mr Benn is transported to Ancient Rome, where he meets his friend Smasher Lagru. But he has forgotten that prisoners are made to fight gladiators in the arena, and those who aren't beaten will end up facing the lions.

Mr Benn helps the crew of a pirate ship, who are determined not to be pirates, turn their Captain into an honest man, and see that he gets a very different sort of treasure for his island: trees from a crew of gardeners whose ship the pirates pretend to capture, but actually rescue, during a storm.

Mr Benn helps a boy outwit an evil man, with the aid of the magic carpet that came with his costume and a little magic courtesy of a genie in a bottle.

The Indians have always beaten the cowboys in a weekly game of hide-and-seek. When Mr Benn joins in as the cowboy to hide, he helps the cowboys to win for the first time by exposing the very clever hiding place of the hidden Indian.

Mr Benn helps King Neptune and his mermaid friend outwit the crews of two submarines, who are out to find and photograph the King's pet sea monster.

Mr Benn helps the animals in the zoo to improve their accommodation by making the townsfolk see that the cages are too small.

A stone-age community live right next to a dusty and dangerous road, frequented by dinosaurs and other prehistoric animals, but want to live in the fresh green countryside. There's just one problem: there are no caves. Mr Benn has the answer; they can build stone huts.

Little Princess Annabella refuses to eat. Mr. Benn realises she is lonely, and helps her find her appetite by inviting all the city's poor hungry children to the Palace for a feast.

Mr Benn and his fellow astronaut visit several weird and wonderful planets.

Mr Benn is asked by a Queen to change her husband's appearance, feeling he is not Kingly enough. However, the spells cast by Mr Benn do not turn out as expected, and Mr Benn eventually convinces the Queen that how the King looks is not important.

Mr Benn and his partner in a balloon race outwit the cheating Baron Bartrum, who ends up becoming the victim of his own scheme.

The circus people are due to perform at a town on the other side of a fast-flowing river, but there is no bridge. Mr Benn suggests that they all work together to build a bridge.

Mr Benn is dressed as a hunter, in keeping with the pet shop and the garden centre he passed on his way to a shop. He doesn't behave like a hunter however. He is apprenticed to another hunter, who claims to be the greatest hunter in the world, and prevents him from killing any of the animals, by claiming they are not enough of a challenge for him. They finally stumble upon a herd of elephants. Mr. Benn gets them to jump up and down, throwing the hunter off balance. He convinces the hunter to sell his rifle, buy a camera and become a wildlife photographer instead.

In this very first episode, Mr Benn has been invited to a fancy-dress party. He dislikes parties, but enjoys dressing up, so he looks round the shops for a costume to wear, but everywhere he finds only ordinary everyday clothes. Turning into a small lane on his way home, Mr Benn comes across a costume shop where he chooses an outfit of red knight's armour. Changing into the armour, Mr Benn passes through another door in the shop's changing room and finds himself in another world. He stumbles upon a dragon, and at first thinks it is someone else in fancy dress. He soon realises his mistake. He learns that the dragon used to be the King's pet, until an evil match-seller started a fire and made sure the dragon got the blame. Mr. Benn helps the dragon regain the King's favour. On returning to his own everyday world, Mr Benn decides he has had enough excitement and won't be going to the fancy-dress party after all. But he tells the shopkeeper that he will be coming back to the shop again soon to try another costume and have another adventure.,