Aarya gets arrested in the murder of her boyfriend Mehul who gets killed on the bus while travelling towards Pune with his friends. Mehul's death occurred due to a pastry which was offered by Aarya to Mehul while they were entering the tunnel. Mehul's best friend Ishan Gupta reveals that he has full trust in Aarya and that she can't kill him instead, he admits that he killed Mehul but does not have any idea about the poison. How did Poison appear on the pastry?