Writing is not a contact sport, but still, if you’re not careful you can hurt yourself.  You might think I’m being flippant, but look at this dialogue and see how dangerous it can be.

“I am turning in the store,” you say.

“Be careful, you’ll knock stuff over.  The store shelves are very full,” your friend replies.

And you have no idea what she is talking about.

Specifically:  “I am turning in the store” indicates that you are already in (inside) the store and you are turning around, possibly knocking groceries off shelves, or making yourself dizzy, annoying other shoppers or a host of other ‘turning’ activities with limbs flailing.  But the one thing you are not doing is turning into the store. 

The word “into” indicates action: entry, insertion.  It indicates direction and movement headed for the inside of a location.   The word “in” is a preposition that specifically refers to a location.  Other examples of location-oriented prepositions are over, under, above, beside, etc. Writers (be they authors, students, or lay people) have the tendency to use the words “in” and “into” interchangeably.  It’s not a terribly serious error, but as has been previously mentioned in this blog:  If something of yours is worth doing, isn’t it worth doing it right? 

Another scenario:  Your house is under water (not hard for many of us to imagine).  Your phone rings one day and a woman with a very pleasant voice tells you that she is buying property in your neighborhood and offers you the amount of money that you need to get out from under your mortgage.  She invites you and your spouse to her office to further discuss this great deal.  Bad things happen at the office.  How would you express this (foolish on your part) doomed situation? 

We waltzed right into the hands of the bad guys.  Or:  We waltzed right in the hands of the bad guys.  The first one is right.  It indicates action, movement.  The second one looks like this . . .