This is an excellent episode that starts the series proper. The plot is imaginative and well thought out. The introduction of Valarie works, while the banter back and forth feels like Eleventh Doctor and his companion. The voice acting is top-notch, with Jacob Dudman giving at great Eleven performance and Safiyya Ingar really stretching their acting as Valarie Lockwood. The overall sound design is what you would expect from Big Finish with a special mention to the music. This release really feels like it would fit in post The Snowman and before The Bells of Saint John.