Earlier this year, 21 highly gifted children aged seven to 11 were selected to take part in a competition run in association with British Mensa, to find the UK's ultimate child genius. Alongside their home lives, the series charts the progress of some of these extraordinary children through the course of the competition. There is eight-year-old Josh, a chess prodigy whose mum Hilary has a grand plan to put 10,000 hours into making him a grandmaster by the age of 13. Ten-year-old Hugo is an outspoken trainspotter who gets frustrated by those who aren't as clever as him. And there is also Shrinidhi, the current World U-12 Scrabble champion, whose passion for words and all things literary extends to her favourite treat, which is sniffing old books.