My Friend has taken Rs 60,000/- from his friend and has given blank cheque signed and stamp paper, he was paying Rs 2500/- as mutually decided orally. Now the person is threating to him on phone that he has his wife MMS clip and he will upload the same in the internet and he has saying that he has given Rs 4.00 Lacs and incorporated the said figure in his writing in the blank cheque. My Friend has lodge police compliant. He has recorded the telephonic conversation in which he is saying about the clip which the person would upload to the internet. Moreover when police asked the person he said that he has told to my friend as he is not paying money and is demanding Rs 4.00 Lacs instead of Rs 60,000/-. Prior to this month when my friend paid him Rs 2500/- as decided he has the signed copy of the same and in which the person has written that Rs 40,000/- left and signed the same. Now he is saying that Rs 4.00 Lacs is remaining, he use to call him after consuming alcohol and mentally harass his demanding that Rs 10,000/- he want within 2 days. We need legal advice and help for it.