"? ? ?" is an original song featuring Yuezheng Ling. The PV references the Super Mario franchise throughout the whole song. There is a talkloid section at the end of the PV. Ling's character plays a video game that uses an 8-bit version of "飞跃乌托邦 (Fēiyuè Wūtuōbāng)" as the music. She falls off the building and lands flat on the ground near a startled Xin Hua, who was singing and playing "? ? ?" on her guitar, referencing "城色 (Chéng Sè)". Referencing the talkloid at the end of "Chéng Sè", Ling hands Xin Hua some tip money and Xin Hua responds to her in an angry and upset tone.