Retribution: 2 (The Terrestrial Twins Mystical Exploits)

The Twins, having recently passed both their 17th birthdays and their driving tests, have again been requested by Merlin to visit Castershire, and along with their parents help solve another problem. Having removed King Offalmire on their last visit, his son Drossmire mysteriously turns up trying to reap retribution, and again the 'Thirteen Treasures of Britain' are also being threatened. The Twins meet and become involved with another set of twins, Arthur and Gwen Dey, who are part of the mythological plan, and who, like Mary and David, also have black and white hair. They then assist the 'Terrestrial Twins', in a gripping and exciting, action packed and magical story, to again become the victors of good over evil with Drossmire's demise.

The Twins reach 17 years of age and are again asked to assist with a problem. King Offalmire's son Drossmire turns up to reap retribution. Again the 'Thirteen Treasures of Britain' are in danger. The Twins meet another set of twins Arthur and Gwen Dey, who are also part of the mythological plan.