fall in with

Verb

 * 1) To join (a group of people).
 * He has fallen in with a bad lot.
 * 1) To meet with (something).
 * 2) To accept, abide by (a set of generally agreed rules, or a suggestion).
 * It seemed like a good idea, so we fell in with it.
 * It seemed like a good idea, so we fell in with it.