Hollywood star Marcia Tait wants to pay the British producers back who did not believe in her talent back then, so she plans on playing the lead in a play of the Bohun brothers. One night, while she stays in their 17th-century pavilion on their property, she is beaten to death and only the footprints of the man who discovered the corpse are found outside in unbroken snow. However Marcia clearly was murdered before it stopped snowing that night. James Bennett, another guest of the Bohuns, calls Inspector Masters and his uncle Sir Henry Merrivale to solve this impossible situation.
Following the first Merrivale novel The Plague Court Murders, this features another one of Carr's classic tricks that in its basic points got modified by both other writers and Carr himself, the latter most obviously in She Died A Lady, which is an overall better novel both due to its plot and trick. He wrote that one almost a decade later so I don't really want to compare them too extensively, but then again it does make for a useful thread through a review.
First off a rather subjective remark though which kind of drifts into spoiler territory concerning the solutions (mark to read): In both novels the solution actually isn't a trick worked out by the murderer to create that seemingly impossible situation by himself. There are several factors both stemming from the culprit, the victim(s) and other characters that constitute the absence of footprints. If I recall correctly Nikaidou Reito also created his murders without footprints like that. This isn't necessarily a bad thing (even though I would like to see a different case), as long as you can figure out these certain aspects for yourself with sufficient clues. She Died A Lady achieved exactly that while the novel discussed here... I'm not entirely sure what to think. There even is a clue that's so inconspicuous it needs a page reference during H.M.'s explanation at the end and the other hints were so arbitrary I wouldn't exactly call their interpretation logical. I wouldn't say the explanation is not deducible, but there is a difference between this and Queen-ish fair play. And it's not like Carr isn't capable of the same. The whodunnit in She Died A Lady actually is a perfect example for that as nobody else could have been the culprit. So all in all the mystery is enjoyable and the solution does not involve a (mechanical) gimmick and is not contrived in any way. The explanation feels very natural and imaginable. It's just the clues and hints that are definitely there but kind of a mixed bag.
Other than that, even though the tone is fundamentally different to The Plague Court Murders, I had a similar problem concerning my personal enthusiasm while reading. Plague featured an eerie setting and the murder happened rather late. Priory's murder happens a bit earlier, but Carr's trademark atmosphere is almost completely absent. Generally speaking I don't mind the latter, but in both books I kind of lost interest as soon as H.M. showed up. And it's not because of his character, but because I simply thought it's way too late into the story where I didn't really care anymore and just wanted to know how it was done. Priory has false solutions and dialogue that keeps you interested, so this might compensate for the lack of atmosphere or interesting setting, but apart from that I enjoyed both books in a comparable manner. Meaning: Definitely not my favorites and I figure I just prefer Carr in the 40s.
I can recommend this as a classic of the no-footprints-variety of impossible crimes, but in general this might not be everyone's piece of cake, just as it wasn't mine compared to other Carr novels I've read recently.
I should read more Queen before leaving the country and my (English) books behind for a year, but thanks to Kagi no kakatta heya (which I'll review once it finished airing) I'm in the mood for locked rooms. As for Carr, I'm rather indecisive concerning what to read next, so I might as well start with some Herbert Resnicow since I can't think of many remaining (full-length) Japanese novels featuring locked rooms I purchased in the past and want to read desperately except one by Arisugawa Alice (ignoring Nikaidou's bricks and Shimada Souji's debut novel which I apparently got spoiled by Kindaichi Shounen...).