This article explores some rare sides of twin research. The focus of this article is the sad plight of the Dionne quintuplets, born in Canada in 1934. However, several other studies belong in this category, such as Dr Josef Mengele's horrifying twin research conducted at the Auschwitz concentration camp, Dr John Money's misguided attempt to turn an accidentally castrated male twin into a female, Russian scientists' cruel medical study of conjoined female twins and Dr Peter Neubauer's secret project that tracked the development of separated twins. Reviews of current twin research span twins' representation of self-image, twins with Kleine-Levin Syndrome, heteropaternal twinning in lemurs and factors affecting risk of dental caries. Media coverage includes a pair of high-society models, a book about the 'Winkelevii' twins, Super Bowl twin teammates, a family with three sets of fraternal twins, a twin sister surrogate and a near presidential twin.