|This article is written from the Real Life point of view|
Sector 1 is a theme in Metroid Fusion, and arguably its best known. It is heard within the sector itself, during the game's introduction sequence, and as part of the Metroid Fusion Arranged Version medley on the Metroid Prime & Fusion Original Soundtracks. On that CD, the in-game track is titled Sector 1 (SRX) SR388 Return Area.
Sector 1 is used in the Metroid Prime 2: Echoes Bonus Disc when Fusion is selected in the Chronicle. A remix arranged by original composer Minako Hamano is also used in Super Smash Bros. Brawl as one of the themes that plays on the Frigate Orpheon stage, as well as during the battle between Zero Suit Samus and Pikachu and the Copied Power Suits in Adventure Mode: The Subspace Emissary. The latter usage acted as an indirect reference to the SA-X. The Brawl remix returns in Super Smash Bros. for Wii U on the Pyrosphere stage. The original version appears in the Samus Archives Sound Selection released with the Special Edition of Metroid: Samus Returns, referred to as Sector 1 (SRX).