The story of Flo and Kay, the worlds only female autistic savant twins. Savantism is a rare condition in which sufferers of developmental disorders, often autism, are capable of acts of genius that far outstrip their expected levels of ability. In Flo and Kays case, they each have extraordinary memories for facts and dates.

Among their many special talents is an ability to compute the day of the week for any date – past or future. For any given day of their lives, they can remember what the weather was like and even what they had for breakfast.

According to psychologist Dr David Holmes, Flo and Kay’s well ordered minds are also reflected in their well ordered lives. The more that they can create order, the more secure they feel, he says.

At 52 years of age, the twins are bubbly and sociable. They are passionate about music, enjoy going to gigs and love to laugh. This means that they do not fit the classic stereotype of autism sufferers.

At the New Jersey Neuroscience Institute, Dr Nancy Isenberg uses the Autism Diagnostic Observation Schedule (ADOS) to perform her assessment. She asks Flo and Kay a series of questions about friendships and emotions. As well as listening to their answers, she observes the sisters’ body language.