I've come across a very unique slider and I am interested in how it is built. I've scoured the web and can not find a pre-made slider like it. I have found similar "sliders" and mucked around with them, but don't come close to mimicking the effect.

The slider I am looking to create can be found here:  http://www.liberal.ca/ any clues as to how this was made? Know of pre-made sample that has the code I can look over and learn? Or can you simply point me in the right direction to figure this out?

Any help is appreciated, thank you.