Madonna thrilled fans at her New York City show on Tuesday by introducing South Korean star PSY as her surprise guest.

The Material Girl was performing her hit Give It 2 Me when PSY appeared onstage via a raising platform, much to the delight of the sold-out crowd of nearly 20,000 at Madison Square Garden.

Madonna then showed off her Gangnam Style moves as the duo gave a raunchy performance of the hit anthem.

She told the crowd that Psy had flown "all the way from Frankfurt, Germany this morning" to join her, and admitted she was a big fan of the rapper.

Before jetting to the Big Apple, Psy hinted about his cameo appearance in a post on Twitter.com, writing, "I think tonight I am going to go dance with a friend and make some history. You will see."