Below are groups of videos that should give you some idea on what you're signing up for.  The official Tough Mudder videos are short, sweet and show a brief glimpse into the event.  The headcam videos show you what's actually in store.

 
 

Videos to watch with a cup of tea:

 

Videos to watch with a sandwich:

 

Videos to watch over dinner:

 

Videos to watch just for fun: