What was initially treated as an accidental death turned into a murder investigation after Ketan Agarwal's sister questioned inconsistencies in Siya Goyal's account of the incident. Her doubts prompted police to reopen the case and examine CCTV footage, which allegedly showed a hooded man following the couple at Lohagad Fort. Investigators found the man's appearance and movements suspicious, leading them to identify him as Chetan Choudhary. Police then pieced together technical evidence, CCTV footage and other leads, transforming the case from an accident probe into a major murder investigation.