Joseph and family are getting ready to begin their journey home when a great hubbub starts. The Magi have arrived from the east seeking the 'one born king of the Jews', having seen his star and come to worship him.
I'm pretty sure we all remember how this went in the Bible?
Herod calls the Magi before him and questions them to find out where the child is, so that he can 'worship' him as well. But, of course, we really know that Herod is threatened, believing this kingship to be a human, material one that he needs to quash to maintain his own throne.
The Magi set out and locate Christ and His family, and worship, gifting the child with gold, frankincense and myrrh. Then, having been warned by an angel of Herod's true plans, they set out for home by a different route.