The Tattoo Murders

When an unidentified dead body is found in the Kamathipura area, the case is assigned to the local PI Aditi Acharya (Meera Chopra). While tracking the case, her past starts to haunt her in the form of a scorpion tattoo. How is it related to her past, and who is the serial killer behind tattoo murders? How are the two unrelated incidents connected is what the series is all about?