Author Trevor Baxendale brings us another great adventure with the Doctor, Amy and Rory. The TARDIS lands in a pigpen on a farm that is having trouble. Once the Doctor, Amy and Rory step outside they find out that that the Innocent little Conway farm is about to have trouble but it's Chris, Jess Conway's soon to be who knows what is going on. Soon the Doctor finds out that the moon rock that Chris had with him turns out to be the reason why most of the English farm has been turned to moon rock. The heart of stone is the vessel in which a being from 4 billion years ago crashed onto the moon. This is a great Doctor Who tale and one that gives Rory a little time with the doctor that he hasn't had before. I highly recommend that if you're a Doctor Who fan that you pick this book up.