This book is an Enid Blyton style adventure story for children, written with the specific intention for it to be fun for kids.

It was originally written in English and published in the second volume of The Young Falcon, a magazine for children published by Valletta Publishing and edited by Tony C. Cutajar. The story ran in nine episodes from October 1989.

The adaptation to Maltese was published by Pubblikazzjoni Bugelli in 1993, and it was illustrated in black and white, the original illustrations for the magazine publication having been discarded.

The underground world created in this book was to be the base on which the multiple underground cities and different layers were built for the PULLU books to come much later.

The blurb on the back cover goes as follows:

Who would have believed that under the Maltese land there is a marvellous world begun by some Maltese hundreds of years ago? Relf, the boy from Tahtlart, meets Isabelle, Paul, Albert and Carmen and takes them to visit his world. But without the children having noticed, they had taken with them two criminals - and they were armed and desperate!