Lily was accompanied by mentor Kelly Rowland as she hugged fans and former classmates outside Teesside High before delighting pupils with a performance.
Meanwhile, Marcus made a grand entrance in Liverpool by touching down in a helicopter, before revisiting his previous day job in Jonathan James Hairdressers and later singing at his old Sacred Heart school.
Fellow finalists Little Mix have also been back to each of their hometowns to perform for fans and thank their supporters.
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