The BBC television show Dragon's Den is based on the Japanese format Money Tigers.
Money Tigers was a Japanese television programme in which entrepreneurs pitched business proposals to wealthy investors. The British adaptation changed the investor nickname from tigers to dragons, creating the title now associated with the UK series.
The central format remained similar: entrepreneurs seek investment by offering a percentage of their company, while the investors question the proposal and negotiate over valuation and equity. This structure has been adapted in numerous countries.
Dragon's Den is sometimes described as the source of Shark Tank, but both shows descend from the same international format family. The Japanese title explains why the UK programme uses a powerful animal metaphor for its investors.