Mother is not letting meet father his son without divorced

Sir/mam We are married for over nine years and one and half year back my sister in law came to our house which is in my wife and mother in law's name in Mumbai and she asked that she want divorce from her husband and since then filing the case she is staying with us .So me ,my wife my seven year old son and my mother in law were staying together .but suddenly one day 6 months back from today my wife asked me to leave her house and kept my son in their custody and filed a complaint that I want to take our son away from her forever.Now after repeated requests she doesn't let me meet my son .Police even did not file any complain from my side as she fed them money.I love my son very much and I only upbring him as my wife was working and I do a part time job so that I can upbring my son in fatherly environment.She mostly stays away from home in meetings and travelling.Also in last six months they have fed my son that his father is evil and bad and will beat him if my son talks to his father.I am struggling from last six months and I did not even speak to my son for only five times .I need help.plz support. God bless