He's known as the lovable entertainer who stole our hearts way-back-when on the very first season of Australian Idol.
After taking the title of Australian Idol in 2003, just beating out Shannon Noll, Sebastian's career has done nothing but sky-rocket. With several hit songs and top-selling albums, as well as a regular stint on the judging panel of Australian X-Factor, Sebastian has dominated the Australian music scene for well over a decade.
Well, if you remember the Aussie crooner as looking like this, you're in for a BIG surprise.
The star has since gone through a major body transformation, and has taken to his Instagram account today to share a very steamy selfie.