More condensed than the Black Widower's Club, these are the `5 Minute Mystery' type stories. And while some are eminently solvable (if you're really smart), there are others that are severely dated. Specifically, the library book mystery - not something the younger generations (especially those living in big cities) would ever get. Still, unless you have to be able to solve them, it's still a fun and worthwhile read. And because they are very short, it's easy to squeeze on in before bed, while waiting on take-out, or in the doctor's office. A great little book to have around for just such time-wasting emergencies.
But if you're looking for really great (if a little longer) mysteries with much better characters, I recommend the Black Widowers series. Even though this book rates pretty high, those are far superior.