You make departure from your home off into the great beyond. You will go to see the unseen, and hopefully make a great discovery.

This is a jukugo word, which usually means on'yomi readings from the kanji. You know the はつ part, which gets shortened to はっ. The 見 is unlike what you learned with 見, though.

In order to remember that this is けん, imagine you're going out to make a discovery of some strange new lands. With strange new lands, there comes strange new people. This one has a samurai named Ken (けん) on it. He's trying to discover new things too!