I think, only JB, Ezbassr, and Centurion are old enough to remember this one; and if so for anyone, please keep it under your fedora for a few days 
A detective broke into an apartment, found Harry and Grace lying on the floor, dead. Beside them was a small pool of water... and some fragments of broken glass. Above them, on a sofa looking down at them, was a pet cat, his back arched. The detective concluded, without further investigation, that the victims had died of strangulation.
How was this conclusion possible?
I thinks I might have some sort of a clue but i might just be fishing for answers
Harry and Grace were fish?
But why did the detective break into the apartment? lol
Very rare tropical fish (ref: DeskSet), the riddle of why the detective broke into the apartment however, is one that was left as an exercise for the viewer
I can tell you this though, it wasn't his place, so he didn't have a key ^_^
Oh my god, I must be as old as Ez and JB - cause I know it