Something black !!!

After Dr. Oshana reached her office, there was a packet on her desk. On the top of the packet, the following words were written,

"Open with a smile."

"Ah !!! Now I know why you acted all grumpy in the morning. You have a knack of surprising people Dr. Nelson."

Dr. Oshana mumbled and started opening the packets with nothing but a smile on her face.

Inside she found a thumb drive and immediately connected it to her system and played the video file contained in it. Two minutes into the video and the smile on her face vanished.

"Why would you do this Dr. Nelson?" 

She mumbled and sunk into her chair, unable to believe that she had been exposed. Her entire career was at stake now and she knew that the end was not going to be good.

She immediately picked up her phone and called up Dr. Nelson.

"Hello"

"Why would you do such a thing to me? Why would you trap me? You told your secret and I told you mine. Then why record it?"