Sam, 36, went backstage at the Apollo Victoria Theatre in London's West End after watching the hit musical.
Incredibly, Sam watched the first ever performance of Wicked seven years ago so was delighted to return.
While behind-the-scenes, the X Factor hopeful was introduced to leading stars Louise Dearman - who plays Elphaba, the Wicked Witch of the West - and Gina Beck - Glinda the Good Witch.
Posing for pictures together, Sam joked that one day she'd love to play a lead role in the musical.
After her visit, Louise showed her support for the singer, who is being mentored by Sharon Osbourne. The actress tweeted: "We're all fans and wish you all the best."
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