The Moody Blues' second album was also their first of what would be a succession of "concept" albums. Inspired by the Beatles' Sgt. Pepper and utilizing the London Festival Orchestra primarily for epic instrumental interludes between songs, Days of Future Passed moved the Birmingham band away from its early R&B roots (as displayed on its debut album with soon-to-depart future Wings member Denny Laine) into uncharted rock territory, making them the early pioneers of both classical and progressive rock. The concept of the 1967 release was very simple, tracing a day in the life from dawn to night, from awakening to sleep. The seven tracks spawned two hit singles--"Tuesday Afternoon" and "Nights in White Satin" (which hit No. 2 four years after the LP's original release) and a prog-rock cottage industry.–Bill Holdship
Sentinels, robots that were created for the purpose of hunting down mutants were released in 1973. 50 years later the Sentinels would also hunt humans who aid mutants.