When the existence of the mythical rainbow orchid comes to light, Lord Reginald Lawrence hires Julius and Sir Alfred to find the fabled flower so he can win a botanical competition and save his estate. But the nefarious Urkaz Grope has other plans and does everything in his power to try and stop them as their search takes them from England to France, and then on to India and the lost valleys of the Hindu Kush.

Julius and Sir Alfred are hired by a rich Japanese woman to discover the whereabouts of a set of missing ancestral samurai armour. Just when they think they've found it, on display at the Victoria & Albert Museum, things turn out not to be as they seem, Julius must follow the trail and find out the truth.