The original Dragon's Den investor panel consisted of five dragons.
When the British version launched in 2005, the panel featured Peter Jones, Duncan Bannatyne, Rachel Elnaugh, Doug Richard and Simon Woodroffe. Entrepreneurs entered the den and pitched to this group, hoping to secure investment in exchange for an ownership stake in their business.
The panel later changed substantially. Simon Woodroffe left after the first series, and Theo Paphitis and Deborah Meaden became prominent later additions. Peter Jones is notable for remaining a regular investor across the programme's long run. The phrase “the dragons” therefore refers to the rotating panel, not a permanent five-person cast.
This fact can be confused with the number of investors in later series, because the programme has used panels of different sizes over time. The original launch format, however, used five investors, establishing the familiar plural panel seen by audiences today.