Where was the comedy?

You're right. I have just finished watching this movie and I didn't laugh once. In fact, I didn't even smile. The supposed humor was, for me, non-existent.

That's not to say that I didn't enjoy watching it - I've seen much worse science fiction, or should I perhaps call it pseudo-science, films.

I think you have to have a very particular sense of humor, yes, but I personally found TTWTH to be an absolute hoot! A dying bigot requests a head transplant and his dying prayer is answered by the head of a black convict! If this is not enough for you, then consider that the dying bigot is played by Ray Milland, or as I like to call him, King of the Potatoes, Ray Milland and the criminal is played by the incredibly likeable Rosey Grier. And I'm sorry, I know this is probably very un-pc, but when Ray goes zooming over that big hill on a motorcycle and hollers "AHHHH!!!! YOU BLACK BASTARD!!!", I just lose it root there. He utters the infamous line with so much sincerity that the movie trespasses onto glory. Almost equally hilarious is when super laid back Rosey refers to his disgruntled partner in crime as "Happy Face "! A true howler classic!