Ryan McCartan (born June 14, 1993) is an American actor and singer. As an actor, he is known for his recurring role as Diggie on the Disney Channel sitcom Liv and Maddie, and for his role as Brad Majors in the 2016 Fox musical television film The Rocky Horror Picture Show: Let's Do the Time Warp Again. McCartan is also known as one half of the pop duo The Girl and the Dreamcatcher. McCartan also played Jason Dean, "JD" in the Los Angeles (2013) and the original off-Broadway (2014) versions of "Heathers: The Musical".
McCartan began his career with a minor part in the stage version of Disney's High School Musical in 2007. In 2011 he was a Jimmy Award winner, the top honor given only to two students at the National High School Musical Theater Awards.
Starting in 2013 McCartan began playing the recurring role of Diggie on the Disney Channel comedy Liv and Maddie. In 2015 he starred in the direct-to-video film R.L. Stine's Monsterville: Cabinet of Souls. In 2016 McCartan was cast in the lead role of Brad Majors in the 2016 Fox musical television film The Rocky Horror Picture Show: Let's Do the Time Warp Again.
In May 2015 Dove Cameron announced that she and McCartan were officially forming a pop duo and would be releasing their first original song. In September 2015, they announced their group's name would be The Girl and the Dreamcatcher, and their first video was released in October 2015.
McCartan was born in Excelsior, Minnesota. His father, Conn McCartan, is the principal at Eden Prairie High School in Eden Prairie, Minnesota. He attended Minnetonka High School in Minnetonka, Minnesota, where he was active in theater and choir.
McCartan began dating actress and singer Dove Cameron in 2013. He officially announced that Cameron was his fiancée on April 14, 2016, but their relationship ended in October 2016. He is currently dating YouTuber Samantha Fekete, known from the YouTube channel Battle Universe and her own personal vlog chabnel.