The Grand Illusion is the seventh studio album by American rock band Styx. Recorded at Paragon Recording Studios in Chicago, the album was released on July 7, 1977, by A&M Records, intentionally choosing the combination 7th on 7-7-77 for luck. The release was a smash worldwide, selling three million copies in the US alone. Some estimates have the album at over 6 million copies sold. The album launched the band to stardom and spawned the hit singles "Come Sail Away" and "Fooling Yourself." The title track also received substantial FM airplay, but was never released as an official single.

Crystal Ball is the sixth album by Styx, released in 1976.