Cleo, who formerly starred in 90s pop band Cleopatra, has channelled Disney character Minnie Mouse and popped a huge bow in her hair.
The singer, 30, has teamed the black and yellow headpiece with a sheer black blouse and funky knee-length skirt, which features a VW Beetle print all over it.
Taking a photo in her hotel bathroom, Cleo also gave us a glimpse of her coordinating yellow ballet pumps.
Sharing the picture with her Voice mentor, will.i.am, Cleo tweeted: "#DressingUp @iamwill "Mini Mouse" is in the house ♡ [sic]"
Cleo is one of two remaining acts in Team Will and will battle it out alongside Leah McFall, Andrea Begley, Karl Michael, Ash Morgan, Matt Henry, Joseph Apostol and Mike Ward.
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