The first season of Code Geass: Lelouch of the Rebellion is set to be broadcast on MBS, TBS, and BS-TBS’ Animeism block in October as part of the series’ 15th anniversary, with the rerun to feature a new opening song and ending song.
The new opening song will be performed by FLOW, who also performed the original first opening song, “Colors.” Meanwhile, the new ending song will be performed by TK from Ling Tosite Sigure (Tokyo Ghoul Season 1‘s “Unravel,” Tokyo Ghoul Season 2’s “karthasis”). The original first ending song, “Yūkyō Seishun Ka,” was performed by ALI PROJECT.
Code Geass: Lelouch of the Rebellion first ran from 2006 to 2007, while the second season Code Geass: Lelouch of the Rebellion R2 aired in 2008. The Sunrise-produced series has spawned OVAs, a film series, and the Code Geass: Akito the Exiled spin-off series, as well as various light novels, manga, and video games. A new anime project titled Gode Geass: Z of the Recapture and a smartphone game titled Code Geass: Gensic Re:CODE were announced in December 2020.
Crunchyroll describes the main series as:
The year is 2017 of the Imperial calendar and parts of the world are uner the control of the Holy Britannian Empire. Lelouch Lamperouge, an exiled Britannian prince, encounters a strange girl known as C.C., who gifts him with a great and terrible power. The Geass. With this powerful ability, Lelouch can get anyone to do as he wills. But the power of Geass: is it a blessing…or a curse?
Source: Code Geass Twitter