The first series of the British Dragon's Den premiered on BBC Two.
BBC Two was the channel associated with the programme when the British adaptation began in 2005. The series combined business pitching with the tension of a studio reality format, as entrepreneurs attempted to persuade investors to fund their companies.
The channel detail matters because the BBC has several national television channels, and programmes can move or be repeated across its network. Dragon's Den became a long-running BBC brand, but its original home was BBC Two rather than BBC One.
The programme should also not be confused with Dragons' Den versions made in other countries. The question refers specifically to the British edition, whose early broadcast history is recorded in its programme article.