The purpose of this play is to score quickly.
It starts off in the traditional manner, with the 1 bringing up the ball. 2 and 3 start in the low post, while 4 and 5 start in the high post.
4 and 5 set screens for 2 and 3, who run to the outside.
In this scenario, 1 will pass to 3 and then take position on the right wing.
Instead of 4 flashing outside when 2 moves over, he stays home in the low block.
5 moves up to the high post to establish the triangle.
Having established the triangle, 3 passes to 5 while 1 cuts to the basket, receiving a screen from 4.
5 will then (preferably with his back toward the basket) pass to 1 for the layup.
If the pass isn't there, 1 will continue through the lane to the weak side, taking 4's traditional triangle position.
4 will continue through the lane to the wing.
5 passes back to 3, re-establishing the triangle.