How Many Cats In The Village?

  I only ask, and this is quite a trivial matter, because on one evening during Dance of the Dead No.6 is showing signs of restlessness - obviously he has not drunk his drugged nightcap!  On the bed is the black cat, No.6 is obviously a cat lover, as it's bed time, and he chooses not to disturb the cat and lies back on the leather recliner.  Then as the lights go out, and the female voice is trying to lull No.6 to sleep with soothing words, he departs the cottage via the French door. Then moments later No.2 enters her office of the Green Dome, and there is the black cat! If it is the same cat, how did it get to the Green Dome so quickly? And why didn't anyone spot the continuity error? And if it isn't the same cat, how many black cats are there in the Village?
BCNU