Ichizu/Sakayume

"Ichizu" / "Sakayume" (一途/逆夢, lit. "The Only Way"/"Contradictory Dream"), is a Japanese double A-side single by King Gnu. It was released on December 29, 2021, by Sony Music Labels (Ariola Japan). Both songs served as theme songs for the 2021 MAPPA film Jujutsu Kaisen 0, with "Ichizu" serving as the opening theme and "Sakayume" as the ending theme. They were performed by King Gnu, who aimed the theme songs to focus on the chaotic relationship between the leads, Yuta Okkotsu and Rika Orimoto, with "Ichizu" having a strong starting point and "Sakayume" being more melancholic.

While the songs were released together, a Blu-ray video was also released featuring more singles from the band. They have appeared in several charts from Billboard Japan. Critical response was also favorable due to how both themes capture Yuta and Rika's tragic relationship, with "Ichizu" standing out due to its speed.