In her autobiography, Agatha Christie described The Seven Dials Mystery as one of her "light-hearted thriller type" novels. She considered these books easy to write, as they didn't require extensive plotting or planning. Christie also referred to this phase of her career as her "plutocratic" period, since she had begun receiving generous payments for American serialization rights--larger than those from the UK and, notably, tax-free.
The Agatha Christie book that this series is based on was widely panned by critics in both the UK and the US.