Legal remedy if wife left husband with child

I am married since 2009 and having 5.5 years old son. My wife has fled away with his male friend (Likely his extra marital affair with him which was caught by me before 7 months). Now my son is not in safe hand since that man character is not good he is also married having twins daughters and separated by his wife. He is not earning also. Now my wife is not responding to my call nor my messages. and I dont know the exact location of her. Now i am ready for her comeback or mutual separation also with child custody to me and visiting rights to her unconditionally. We both are hindu. Please suggest me next course of action. How much possible to get child custody from her?