And So to Murder (1940)
My review:
This is eminently unsatisfactory Carr. It is full of what the author believes is 'humour', but which the reader finds tedious; almost as tedious, in fact, as the 'stock' characters. The plot is of a looseness to rival Ellery Queen; the murder device is impractical and improbable; and the murderer's identity is decidedly unfair, and can only be called C H E A T I N G—put into the past tense, this admirably expresses the reader's feelings.