David Mitchell is joined by Marcus Brigstocke, Holly Walsh, John Finnemore and Rufus Hound, who lie on the subjects of board games, salt, guinea pigs and actors.

The Truths

Marcus Brigstocke - Board Games

- The longest ever game of Monopoly lasted 1,680 hours, or 70 days straight. Found by Rufus.

- The number of possible moves in a game of chess is larger the total number of atoms in the known universe. Chess moves equal 10 to the power of 120 and the total number of atoms is 10 to the power of 80. Found by John.

- The longest game of chess lasted over 50 years. It was a game of postal chess between Dr. Munro MacLennan and Laurence Grant that began when they were both university students in Scotland in November 1926 and finished in the 1980s. They wrote their moves to each other at Christmas. Found by Rufus.

- Chess boxing is a sport that involves 11 alternating rounds of chess and boxing. Found by John.

- In Finland a board game called "How to Make Children" was launched to interest teenager boys in the reproductive side of sex. The aim is to land on a "fertility square" in mid-ovulation. It was invented in 1996 and the inventor said that in the game that everyone gets pregnant, even the boys. The game features special sperm and egg dice. Found by Holly.

Holly Walsh - Salt

- In the original series of Star Trek Dr. McCoy's medical scanner was made out of a salt cellar. The first episode of the first season, "The Man Trap", involved an alien creature that craved salt. Gene Roddenberry asked the props department to make some futuristic-looking salt cellars to be made, but upon seeing them he was convinced they were so exotic-looking that the audience would not recognise them as salt cellars, and thus all eight of them became Dr. McCoy's medical equipment. Found by Marcus.

- According to the OED in the 16th and 17th centuries the word "salt" also meant: "sexual desire or excitement, usually of a bitch." However, a recent discovery from the Wiseman Institute in Israel claims that women's salt tears contain chemicals that reduce sexual arousal in men. Found by Rufus.

- Salt, or to be more exact the salt baking soda, and vinegar can make a rudimentary explosive. Successfully smuggled.

- In the African version of the story of Hansel and Gretel the witch's house is made out of salt, because salt is considered a delicacy in parts of Africa. Successfully smuggled.

- Victorian children were often given salt cellars as a sign of being a grown-up. Successfully smuggled.

John Finnemore - Guinea Pigs

- A historically inaccurate painting of the Last Supper in Cuzco Cathedral, Peru, shows Jesus and the disciples eating roasted guinea pigs. The disciples also seem to be drinking a fermented maize beer. It was painted by local artist Marcos Zapata in 1755. Found by Rufus.

- It is illegal to own only one guinea pig in Switzerland. This is because guinea pigs are social animals and thus get lonely without companionship. There is a guinea pig matchmaking service in Switzerland that allows owners to rent another guinea pig if they only have one left and thus stop them from breaking the law. Found by Rufus.

- Theodore Roosevelt made a guinea pig an admiral. The names of his five pet guinea pigs were Admiral Dewey, Dr. Johnson, Bishop Doane, Fighting Bob Evans, and Father O'Grady. Found by Rufus.

- Early guinea pigs, or rather the ancestors of guinea pigs, were the size of bison. In 2003 archaeologists in Venezuela discovered what was nicknamed "Guineazilla", the 8 million year old remains of a creature that had 20cm long teeth and was thought to be semi-aquatic. It roamed in packs and dined on sea grasses. Scientists believe it died out because it was so large it was hard for it to escape danger. Successfully smuggled.

- Folk doctors in the Andes use guinea pigs to detect illness as they believe that the animals are a supernatural medium. The doctors rub the guinea pigs against the patient and believe the guinea pig will squeak when near the source of disease. The doctor then cuts open the guinea pig and examines the entrails to learn more. Successfully smuggled.

Rufus Hound - Actors

- The first ever actor was the ancient Greek Thespis of Icaria. Aristotle says he was the first to use solo speaking actors from the narrative chorus. Found by Holly.

- Before the term "actor" the word used to mean someone who performed on stage was "hypocrite". This was used up until the 15th century. Found by John.

- The Swedish version of the phrase "break a leg" is "a kick up the backside". The French instead says "merde", because if you were a popular actor in the days of horse-drawn carriages, people would be travelling long distances to see you. So horses would be outside leaving manure and audiences would trod in it on the way into the theatre. Found by Holly.

- Thespis of Icaria was also the first actor to use stage make-up. Successfully smuggled.

- EastEnders dog Wellard is a full member of Equity and appeared in the film Gladiator. Successfully smuggled.

Scores

- Rufus Hound and Holly Walsh: 4 points
- John Finnemore: 2 points
- Marcus Brigstocke: -3 points