The Secret of the Unicorn (the Adventures of Tintin)

The visual storytelling adds a lively energy to Tintin's adventures. I wonder if the format was chosen to make it more accessible or for artistic reasons.

The balance between action and mystery kept me hooked without feeling rushed. Was this intentional to suit a younger audience?

Hergé was known for meticulous planning, but I'm curious whether the plot evolved during creation or was mapped from the start.