Ashley Coulston is a cold-blooded killer - possibly “one of the most dangerous Australia has ever had”. But could he be responsible for the deaths of even more innocent victims? Michael Usher's Sunday Night leads a major investigation spanning two years that will reveal new details that will change everything. This story originally aired 16 September 2018. *Connect with 7NEWS Spotlight online* Visit 🔗https://7news.com.au/spotlight 7NEWS Spotlight Podcast 🎧 http://smarturl.it/7NewsSpotlight Facebook https://www.facebook.com/7newsSpotlight/ Instagram https://instagram.com/7newsSpotlight/ TikTok https://www.tiktok.com/@7news.spotlight 7NEWS combines the trusted and powerful news brands, including Sunrise, The Morning Show and 7NEWS.com.au, delivering unique, engaging and continuous coverage on the issues that matter most to Australians. Watch 7NEWS nightly at 6pm and weekdays at 12pm and 4pm on Channel 7 and 7plus.