In 1960, shortly after completing Tintin in Tibet, Hergé began developing a plot line on the basis of a December 1957 article from Marie-France.
"[2] Unwilling to abandon a good idea, Hergé planned to make Le Thermozéro the plot of the third filmed adventure of Tintin but once again, this did not take place.
[citation needed] Bob de Moor, Hergé's assistant, was asked to change the synopsis and make it the sixth Jo, Zette and Jocko adventure.
After a few sketches were made this project fell through as well, as Hergé asked Bob de Moor to modernize The Black Island instead.
In March 2014 it was revealed that de Moor had indeed written a complete script for Le Thermozéro and that more pages had been pencilled before the project was shelved.