Watchers of 'Masked Singer' know that Sandeul couldn't help but sob when he recognized Kim Yeon Woo's voice, and explained that he fostered his dreams of being a singer while listening to Kim Yeon Woo sing. He sang Toy's (Kim Yeon Woo's group) "Are You Still Beautiful" with Kim Yeon Woo.

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It was also surprising to see Sandeul's new hair - he'd been sporting dark hair for the past few weeks, but when he unmasked, he revealed his bright pink hair! Do you think B1A4 could be preparing for a comeback? Check out the clip above!