- The panel are shown a creature and are asked where it lives. It lives on the tongue of a fish. The tongue-eating louse lives on the tongue of the African blacktail fish. It latches onto the tongue, sucks the blood out to such an extent the tongue disappears, and the louse replaces the tongue. The louse lives in the mouth and breeds via the fish's gills. Correction: Dara claims that fish do not have tongues, but this is dismissed by Stephen. However in Series I, Episode 10 ("Inland Revenue"), it is revealed that Dara was right in the first place. Fish instead have a "basihyal", which has no taste buds and is not a muscle.
- Tangent: There is a flatworm that inserts itself into crabs and grows through all the parts of the crab until it pops out of the top and then drives the crab around.
- The thing that is covered in snot and eats whales is a snot flower or muca flora. When the bones fall to the bottom of the ocean it enters the bones, fires plumes and feeds off the nutrients. It gets the name because it is covered in mucus.
- Tangent: Having a tapeworm does not make you hungrier. It only eats a small amount of your food, but it makes you feel sick. Due to irritation of the bowels and other parts of the body you actually lose appetite. 8% of people in the UK have tapeworms, which makes them more popular than dogs domestically. Having tapeworms has benefits, because it can get rid of asthma and eczema. Tapeworms can grow up to be 50 feet long and can live for 20 years.
- XL Tangent: When Dara was 16 a woman he was chatting up told him that in order to get rid of a tapeworm you have to starve yourself and then wave a steak in front of your mouth.
- Tangent: There is another type of worm which can only be taken out over the course of 3 or 4 weeks because you have to wrap it around something like a pencil. You have to go the doctors every day and they will do about an inch a day. There is a theory that this worm is the origin of the medical symbol of the coiled serpent.
- The key ingredient to the world's nastiest cocktail is a human toe. The speciality of the Downtown Hotel Bar in Dawson City, in the Yukon of Canada is the Sourtoe Cocktail. It began in the 1960s when Captain Dick Stevenson found a picked toe of a rumrunner in an old cabin. He thought it would be fun as a dare to drink a cocktail with the toe in it. The drink does not have to be alcoholic, but there is a rhyme which contains the main rule when drinking the cocktail: "You can drink it fast, you can drink it slow, but the lips have got to touch the toe." There have been accidents. In 1980 local miner Gary Young accidentally swallowed the toe. However, a woman from Alberta called Mrs. Laurence donated her middle toe which had been amputated because of an inoperable corn. Now many other people donate their toes to the bar. An estimated 35,000 have drunk the cocktail and costs C$5 a shot. (Forfeit: Malibu)
- XL: One good reason to put a frog's bottom in your mouth is to drink it. The water holding frog (Litoria paltycephala) is an Australian frog which contains a lot of water in it, so if you are stuck in the desert you can suck the bottom of the frog and drink what is very weak urine to keep you alive. It was first discovered by the Aborigines. In the summer the frog buries underground sleeps for several months. This is the opposite of hibernation (sleeping through the winter) known as "estivation".
- The best way to get rid of a leech is to just leave it until it is full. After 10 minutes it will be full, stopped the blood flow, and will leave the body. While it is untrue that ripping off a leech will result in part of it being left behind, the leech uses an anticoagulant to prevent the blood from clotting, so removing the leech will result in the wound not healing quickly and a loss of even more blood. The leech will seal off the wound when finished drinking about a teaspoonful. Burning the leech will make it vomit which may result in other blood it has collected going into your body. Leeches normally attach themselves to the legs and have not evolved to drop down onto your neck. Anticoagulants like those of leeches are being studied in a hope of providing haemophilia treatments. There is still a leech farm in Wales and the NHS uses them in microsurgery. In the Middle Ages the way of catching leeches was to go into the water and have them attached themselves to your legs. Doctors were known as "leeches" and it was one of the most common treatments at the time. Of all the medical treatments which involved letting out blood, leeching was the safest, although they used about 50 in one treatment. Cutting veins (phlebotomy) was the worst. (Forfeit: Don't pull it off, part of it gets left behind; Burn it off)
- XL: A really horrible way of transporting the smallpox vaccine was to give it to orphans. By the early 19th century vaccination had been developed by Edward Jenner, who discovered that injecting people with the minor illness cowpox prevented them from getting the deadly smallpox. In 1803 the King of Spain's son died of smallpox, so he decided to vaccinate everyone in Spain's colonies in South America. In order to transport the vaccine over in a journey that would last several months orphans were rounded up and one was given the vaccine. This orphan developed the immunity. Then you take their blood and put it in the next orphan who develops the immunity and repeat the process with the rest. This meant that the orphans could be used as a serum. The British did a similar thing with low caste Indian boys. The technique worked, but the Spanish orphans were now far away from home, but it could be argued that they had a better future in South America.
- XL Tangent: Smallpox is almost extinct. It was very close to being extinct, but then in 2002 it was thought that humans did not have the right to wipe it way from the face of evolution, so now there is just one tiny amount of it left. There is also the fear that someone else has a smallpox sample which could be used as a biological weapon and so if you have a spare sample you could still make a vaccine.
- XL Tangent: You were more likely to get a job if you had smallpox scars in the 18th century. This was because the scars proved that you already had smallpox and so could not pass it on to your employers.
- XL: The panel are asked to fill in the blanks from 19th century travel books. Answers are in bold.
- "Never rub your eyes except with your elbow." Taken from a handbook for travellers in Spain by Richard Ford in 1847.
- "Keep a spare jewel in case of emergencies in your arm." Taken from The Art of Travel; or, Shifts and Contrivances Available in Wild Countries by Sir Francis Galton in 1872.
- "Beware the dirty habits of the native cooks, who will often be seen buttering toast with the greasy wing of a fowl." Taken from Hardships in Travel Made Easy.
- "The Germans are the worst offenders, having a grossness in their way of eating and a gloating zeal in collecting salacious postcards." Also taken from Hardships in Travel Made Easy.
- You can tell if you have Bonnie and Clyde Syndrome if you are sexually attracted to dangerous and violent people. It is believed by some that Bonnie Parker of Bonnie and Clyde may have had it, with people claiming she was attracted to Clyde who was a really violent criminal and committed murder. Many of the other gang members said that Bonnie never raised a gun. Bonnie and Clyde Syndrome, also known as "hybristophilia" is a paraphilia - a sexual attraction to something unusual like a fetish - which is unusual in that it is one of the few that woman suffer more from than men. In Britain, there is estimated to be at least 100 women engaged to American men on death row. Reasons for the attraction include glamour of notoriety, a like of violence and religious favour (some evangelical Christians who think they can convert criminals). One case reported was of two Christian Australian sisters who left marriages they were already in and married two violent criminals. One was battered to death with a hammer as soon as he was let out of prison. The other was sent back to jail after he tried to cut off her ear and pull her teeth out with pliers. Another unusual paraphilia, harpaxophilia, is a sexual attraction to being robbed.
- - XL Tangent: Dara recalls a documentary that he saw in which a man had a sexual relationship with his car. The people filming the documentary then got him together with another man who had the same fetish. This meeting resulted in one of the men having sex with the other man's car, who got furious with the "adulterer".
- The pizza topping that eats insects is tomatoes. Tomato plant stems are hairy and can trap insects which then die. The insects drop to the ground and the plant absorbs the nutrients from the now richer soil. (Forfeit: Anchovies; Pineapple)
- XL: The panel are shown the picture of unusual looking plant and are asked what it eats, which was something which King Louis XIV ordered to be removed from Versailles once a week. The answer is faeces. Nepenthes lowii, a type of pitcher plant attracts a shrew by giving out a sweet buttery smell. The shrew sits on it, licks of the sweet smelling nectar and defecates while it eats. The faeces give the plant between 70-100% of its nitrogen. During King Louis XIV's reign people did not bathe so when visiting Versailles they defecated in a corner. Louis was a hygienic man by standards at the time and ordered the faeces to be removed from Versailles once a week.
- The first hecklers came from Dundee. The word "heckle" means "comb" and is used for dividing two types of fabric or flax for making yarn. The people who did it were known as "hecklers". Hecklers from Dundee were considered troublemakers, causing violent arguments and debates. This is where we get the modern meaning of the word.
- Tangent: Alan claims he does not really get heckled, but he knows it is bad when people talk to themselves. For example, he was once at the Comedy Store when he spotted one woman turning to another on the front row and saying: "He's losing it.'
- Tangent: Dara once did a stand-up routine in Liverpool about dreams and a member of the audience once said that he had a dream about Kate Winslet. Dara asked if it was a sexy dream, and the man said: "No, she turned me down." Dara then asked if he was disappointed and the man said: "Nah, I didn't hit her with me best stuff." Alan then reveals that he once had a dream with Kate Winslet too and his dream did not work out well either.
- The tail of a snake begins after its bottom.
- The dimensions of a piece of two by four are about 1.5 x 3.5 inches. It is based on a dimension block which was originally itself two by four, but it is then shaved and planed so it becomes smaller. However, even now the dimension block is of various sizes, both larger and smaller. A two by four is just simply a block of wood. (Forfeit: 4 x 2; 2 x 4)
- What is the following a description of: "Allegedly it can cause birds to fall dead from the sky, and it is banned by airlines, but it is quite good on toast." It is Scandinavian rotten fish, known as "surströmming". Stephen has a tin of it, but is ordered not to open it because the smell is so awful it would never leave the studio. It involves putting herring in a wooden barrel with about half the amount of salt you need to cure it. The herring ferments and putrefies. After about a month you can it, in a can designed to swell up slightly because it is still fermenting. The smell is said to be the worst in the world. Often the can is opened underwater to stop the smell, because the way to eat it is to rinse it then cover it with onions which help with the smell as well. A story goes that in the 16th century some Swedish sailors ran out of salt and had this fish rotting. They found some Finnish islanders and sold it them thinking they would be stupid enough to eat it. A year later they came back and the Finns asked for some more. Learning it tasted good they made some more.
- Dara O'Briain: 2 points
- Chris Addison: -13.8 points
- Sean Lock: -33 points
- Alan Davies: -35 points
Including the unbroadcast pilot, this episode was the 100th QI instalment.