Let's start on a positive note...the fight scenes were brilliant, certainly the funniest parts of the movie. A bunch of drunks that can kill robots...not robots with action movie style and professional wrestling moves is almost too funny to watch.
Seeing Pegg and Black's characters interchanged was fresh as well, especially since Black pulls off the lovable Pub king and Pegg does a good job of looking like an old alcoholic.
And the last determined dash to hit the final two pubs was classic...
...but not of the same caliber as the previous two in the unofficial trilogy.
The alien thing was too...meh. Invasion of the Body Snatchers with an awkward Dreamcatcher vibe and it didn't work.
In fact, for the most part, a lot of it just took away from the humor as a whole. The build-up was a bit of a downer and by the time the comedy hit, the audience was gone.
The fun came too late in the film and for a long time it seemed like a drama with an amused grin and not the comedy that you'd expect.