The boy-girl duo stood out among the boybands and power ballads at the weekend and were dubbed the "new N-Dubz" by Louis Walsh, a man who knows a thing or two about urban music (possibly).
Watch our interview with MK1 below:
Digital Spy caught up with Charlie and Simeon to talk about their musical expertise (guitar, piano, grade 8 drums), ask why they took on The X Factor ("It's a different look this year and it's become more credible") and find out what was happening backstage last weekend ("It was absolutely mental!").
The pair also spill some gossip about their relationship with their mentor "Uncle Lou".
"Louis Walsh understands what we're trying to do. And for him we're a breath of fresh air," says Simeon. "We're going to teach him some more stuff about rap... By the end of the series he'll be ready to rap."
The X Factor continues on Saturday night with a 'Love & Heartbreak' theme.
Watch MK1's first performance below: