Here is what Simran Singh had to say about this movie:
Since the death of her parents, Bani (Waheeda Rehman) has lived with her cousin Maya and Maya's husband Mohan Rai. Unhappy with the way Mr. Rai treats her, she gets a job as a secretary in a lawyer's office and moves in with her uncle. The lawyer, Ajay (Guru Dutt) turns out to be the uncle's downstairs neighbour and soon he and Bani are in love.
But when Maya is murdered and Bani accused of the crime, Ajay - and his sidekick Moti (Johnny Walker) - must prove her innocence. The viewer already knows who killed Maya and why, the suspense comes from wondering whether Ajay and Moti will figure it out, and whether they will do it before the murderer strikes again.
The quality of the print is very bad - some scenes were so dark that it was almost impossible to tell what was going on. But the chemistry between Waheeda Rehman and Guru Dutt is breathtaking. This is actually the first movie I've seen him in where I found him physically attractive. And the songs are great (but unfortunately unsubtitled). There's even an item number featuring Helen, who must have been about 19 at the time.