I have been known as the Bosun for many years even though I never sailed in an unlicensed capacity. It was because of my big interest in marlinspike work and small boats. Along the way I learned to tie a really good looking and apparently complex knot behind my back. This is a great trick to have in your knot skills bag. It can be used to impress, or becalm others in a group, depending on their skills and egos.
Here is the picture of the finished knot. I guess that it would be called a sheepshank with a modified square knot layed up in the middle.
Use a piece of line that is flexible but not limp when you tie it. Use line of less than half inch diameter unless you are laying it up on a table top as a demonstration.

Simple things often give the best results.

Make a simple loop as shown with the standing part on top.

Repeat with another similar loop placed UNDER the first.

Repeat the looping process until there are four of them in the stack. Note that each is placed under the one before it.
It is like laying up a four loop clove hitch.

This is the hard part to do behind your back and will take a little practice.
Reach through the outer loops from both sides and grab the THIRD strand. This is why it is hard to do with a line that is too limp.  -

Carefully draw the strands back through the outer loops while also holding the standing parts. This will cause the square knot to form and draw up the cinch loops on the long ears of the main knot.

If you have been careful, you can now pull the finished knot from behind your back to the applause and envy of everyone in the room. All the knot lovers anyway.

Have fun.

Cool Knots - Thanks for the Input kpbosun!

KPBosun: would you drop me a line via email?  Your contacts page shows no email for me. Use my contacts page.