In 1989 Cai commenced his "Project for Extraterrestrials" series, which involved large-scale explosion art. The project went on for 10 years, during which period he finished a total of 32 of these works. The series served as a watershed in Cai's career as he moved from explosion paintings toward adopting three-dimensional space as his canvas.
從 1989 年開始，蔡國強以《為外星人作的計畫》為名進行大型爆破藝術，這個持續 10 年、總計有 32 項計畫的大系列，是蔡國強從平面的火藥炸畫，走向以立體空間為畫布的分水嶺。