Arthur Gask's 'The Hidden Door' is a gripping mystery novel that delves into the realm of psychological suspense. Set in the backdrop of a secluded English mansion, the story unfolds with intricate plot twists and well-developed characters. Gask's writing style seamlessly combines elements of classic detective fiction with a psychological intensity that keeps readers on the edge of their seats. The atmospheric descriptions and cleverly crafted narrative add depth to the story, making it a compelling read for fans of the genre. 'The Hidden Door' stands out as a defining work in Gask's repertoire, showcasing his talent for creating suspenseful and engaging mysteries that leave a lasting impact on the reader. It reflects the author's deep understanding of human nature and the intricacies of the human mind, offering a unique perspective on the genre. I highly recommend 'The Hidden Door' to readers who appreciate well-crafted mysteries that challenge their intellect and keep them guessing until the very end.