Its called a "heater matrix !"..and just like the film, its very confusing ...The pipe itself is pretty small...but twists in a wierd kinda way...
Also expemsive to replace..( lost mine ona BMW ! )..
If you can get hold of one through a scrap yard...pay a mechanic £30 to fit it..its a lot easier !
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix cars.