This is a great, short piece of mystery.  It's the classic "locked house, dead body, 5 suspects" genre of murder mystery done in an infocom style --complete with Sgt Duffy. 
 
For me, just coming back to the genre after many years, this was a great intro.  It's got a simple map with around 10 location, not too many objects, some modest red herrings and a good *logical* story.   
 
Not to mention that, if you do get stuck, there are built-in clues.  All this makes for a good easy game for newcomers also. 
 
The actual who/how/motives are randomized, so there's some replay value, though some of the fun is really in the first time.