The Den's five multimillionaire investors probe the money-making potential in wearable maps, interference-free guitar cables and an entrepreneur with a business selling manhole cover keys that has come back from the brink of bankruptcy. Will it be second time lucky for the plucky entrepreneur, or will he see his investment hopes go down the drain?

Tensions are running high as an entrepreneur ruffles some feathers in the Den when he fails to clarify his restaurant business model, a husband-and-wife duo fight to defend their innovative drilling tool gadget, and it is sink or swim for a businessman pitching his portable water-saving product. But will any of the Dragons see the potential in his eco-friendly design, or will they wash their hands of it?