There is a non remote possibility that it is a typo for: "Crime files"

The saying is a pun. The usual saying is "time flies" which just means that time goes by fast. In the pun with Batman, "crime flies" is a play on words that doesn't really mean anything except in this context where Batman is referencing how fast time has gone by as he was fighting crime for three years. Hope that helps!

Do you have more context, perhaps the preceding sentence?