How do you rate Doctor Who: The Invisible Enemy? (5=Fantastic)

This is a tough one - - - it's got a dodgy monster with a terrific catch phrase, but he doesn't show up until halfway through the episodes....until that point it's a pretty spiffy 'base under siege' episode, even despite the snowy glitter dabbed about the eyes of those 'compromised' by the swarm....and hey - it's got Admiral Ozzel in it to lend a bit of respectability to the proceedings.  4 tardis groans from me.