Deadpool star Ryan Reynolds shocks fans with bizarre appearance on South Korean singing show

Ryan Reynolds has made a bizarre appearance on a South Korean TV show, dressing up as a unicorn and singing the classic Annie tune Tomorrow in front of a live studio audience.

The American actor was in the country to promote his upcoming film Deadpool 2, that also stars Kiwi actor Julian Dennison, when he decided to put in a surprise performance on the King of Mask Singer show.

Adorned in an elaborate cartoon unicorn mask and cape, 41-year-old Reynolds looked at home as he belted out Tomorrow to a rapt audience.

"Hello, everybody. I'm so sorry about that song," he told the audience after he took the mask off and revealed himself to a roaring crowd.

The star also admitted that "I didn't even tell my wife," about his surprise appearance on the show, although it's likely she knows about it now.