The original title of the UK television show’s first series was Dragons' Den.
The title uses the plural possessive form “Dragons'” because the programme’s investors are collectively known as the dragons. It refers to the traditional image of a dragon’s lair while signalling that several investors occupy the panel.
The apostrophe is sometimes written incorrectly as “Dragon’s Den,” but the established UK programme title is “Dragons' Den.” The format should also be distinguished from Shark Tank, the American adaptation, and Money Tigers, the Japanese programme that originated the format.
The British series premiered in 2005 and has retained its central title despite changes in broadcaster scheduling and investor line-ups. The title therefore identifies the UK edition itself, not a particular series, dragon or investment deal.