The remaining contestants got a chance to explore the city this week, ahead of their big performances on Sunday night.
Karabo, Rhema, Siphelele, and Mmatema hit the streets of London for a few days.
They took pictures with a famous red telephone booth, went shopping, took a ride on the London Eye, and even got to see Buckingham Palace during a tour bus ride.
But it wasn’t all fun and games. The top four were mentored by British singer Ben Haenow, who gave them advice for their next performances.
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Ben was the winner of X Factor 2014.
It looks like the contestants had a blast in London, with Karabo describing the trip as a life-changing experience.
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Image credit: Idols SA/ DSTV