From Longman Dictionary of Contemporary Englishbe/get in on somethingbe/get in on somethingINCLUDEto be or become involved in something that is happening I think you ought to be in on this discussion, Ted. → in
Examples from the Corpus
be/get in on something• The kind of place not to be in on a Sunday afternoon.• An outside linebacker, Abe enjoys the position because he can be in on every play, pass or run.• Even small independents are getting in on the act in a modest way, though.• We had to make the game all-ticket so no-one came thinking they could get in on the day.• That is neither right or wrong; we both have an interest and both want to be in on the decision.• Leese was getting in on the other side, and my cyclic stick moved as he bumped his with his leg. 