Captain Haddock home, Marlinspike Hall (or "Moulinsart" in the original French). Harry Thompson, author of "Tintin: Hergé and his creation", writes that the introduction of this large and luxurious country house was "to provide a suitable ancestral home for Tintin and himself to move into." To achieve this in terms of the plot, Hergé also details Haddock's ancestry, something Thompson regards as distinctive: "Haddock is the only regular character whose relatives turn up in the Tintin stories at all (if one discounts Jolyon Wagg and his dreadful family)." As Haddock's role grew, Hergé expanded his character, basing him upon aspects of friends,
The Secret of the Unicorn Haddock was "the best realised character" in the story, conversely describing the Bird Brothers as "relatively uninspired villains". They went on to state that "The Secret of the Unicorn"-"Red Rackham's Treasure" arc represents "a turning point" for the series as it shifts the reader's attention from Tintin to Haddock, who has become "by far, the most interesting character". They praised the "truly outstanding storytelling" of "The Secret of the Unicorn", ultimately awarding it a rating of four out of five. Phillipe Goddin commented on the scene in the story in which Haddock relates the life of his ancestor, stating that