Though with possibly not the most authentic Germanic accent you’ll ever have heard, “Holmes” (Basil Rathbone) still manages to smuggle Swiss scientist “Tobel” (William Post Jr.) back to London where we learn that he has developed a game-changing bombsight that could turn the war in the allies favour. He’s a bit of an enigmatic chap, this man, and declines all the security offered him so it’s no great shock that barely a day after his arrival, he has been kidnapped. Fortunately, he had the foresight to split his apparatus into sections and now the race is on between the detective and his stalwart “Watson” (Nigel Bruce) against their most formidable antagonist yet - “Prof. Moriarty” (Lionel Atwill). Determined to track down his nemeses, “Holmes” heads off into the fog to find the prisoner, but his foe has already anticipated many of his movements so it is lucky that “Watson” and the much less hapless than usual “Lestrade” (Dennis Hoey) are on hand to help thwart this dastardly plan for not just the nation, but for their friend, too. This has a much more overt wartime message to it, with the Nazis the real evil that would benefit from this ultimate act of treachery. Along the way there are some secret compartments, some bumps on the head and quite an ingenious method of attempted murder facing our duo, and it’s an easy hour of mystery to watch. I really do wish they’d stop referring to Britain as England, though!