Did you notice?

At the end of the story Fred unmasks The Witch Doctor and the Zombie Nurse. So how does that explain the Mutant receptionist that was running about in chapter three?

Also in Chapter three. Velma asks "Shouldn't you use chlorophyll Dr Shaggy?" She should really be asking about Chloroform as chlorophyll is what makes leaves green! Maybe her mind went dead.

Chapter six is the only time we see Dr Trembler in his true form as he was supposedly kidnapped at the beginning of the story. I guess they haven't seen him earlier in the episode.

Shaggy says that they wouldn't let Scooby into Dr Trembler's surgery last time they came. He shouldn't be surprised, as Scooby should have gone to the vets!

Did the doctor really make footprints when he stepped in the puddle? If you think about it, he would just make wet marks.

The haunted hospital became haunted very soon after it was abandoned so is it a surprise some crook made it a base for his illegal animal testing?

Seeing as Shaggy's dodgy heart made Fred's trap go wrong, isn't he lucky that no one sent him back to a doctor's surgery?

Talking of which, how exactly was Shaggy magically resuscitated while flung over Fred's back?

It's funny in Chapter three when Shaggy is asking for strange objects to operate with as none are found in a Hospital. So where did they come from?

Velma needed Shaggy to get her away from the witch doctor because she had plaster of paris on her feet. She obviously couldn't move in it so

A) How did she change into Doctor's clothes? B) How did she 'hop' onto the trolley?

1. Fred failed to notice he was leaving Daphne behind when he closed the door to the store cupboard, despite the fact he was standing right next to her at the start of the chapter. That's pretty careless!

1. When Fred's trap went wrong, he mistook Scooby for 'the' ghost. A ghost was never mentioned in the story.

1. End of Chapter three: 'Scooby zoomed through an open door into an old laboratory'. This would certainly be an exception as the rest of the laboratories are underground!