Cigars of the Pharaoh
"The Secret of the Unicorn" was the first half of a two-part story arc that was concluded in the following adventure, "Red Rackham's Treasure". This arc was the first that Hergé had utilised since "Cigars of the Pharaoh" and "The Blue Lotus" (1934–36). However, as Tintin expert Michael Farr related, whereas "Cigars of the Pharaoh" and "The Blue Lotus" had been largely "self-sufficient and self-contained", the connection between "The Secret of the Unicorn" and "Red Rackham's Treasure" is far closer.