Phir Tauba Tauba.

Three boys named Bunty, Happy and Lucky, study in a London school. They fall in love with three young girls. The boys then happen to meet Rubina, a very attractive young lady who is married to Khan. Rubina leads the boys down the garden path and tells them that her husband is very troublesome and that if they killed him for her, they could all have a good time. The boys make several unsuccessful attempts to kill Khan. Finally, they are ready to admit their failure and unwillingness to carry out the crime. But they discover that Khan has really been murdered and that they are the accused in the homicide case.