Imaginos is the eleventh studio album by the American rock band Blue Öyster Cult. It was released in 1988, and was their last recording with their original record label, CBS/Columbia Records.

The album took nearly eight years to complete and was originally intended to be the first in a trilogy of solo albums by Blue Öyster Cult drummer and songwriter Albert Bouchard after he was fired from the band in August 1981. CBS rejected the album in 1984, but a re-worked version was eventually published as a product of the band. Many guest musicians contributed to the project over this eight-year span, including Joe Satriani, Aldo Nova, and Doors guitarist Robby Krieger, but some band members were barely involved in the recording process. Thus, Imaginos is often considered more as a project of producer and lyricist Sandy Pearlman than as a true album of the band.

Imaginos weaves scripts and poems by Pearlman, dating from the second half of the 1960s, into a concept album and rock opera about an alien conspiracy that is brought to fruition during the late 19th and early 20th century through the actions of Imaginos, an agent of evil. The tale combines elements of gothic literature and science fiction and is strongly inspired by the work of H. P. Lovecraft. Subtitled "a bedtime story for the children of the damned", it has an intricate storyline whose often-obscure lyrics contain many historical references, prompting speculation by fans and critics. It is often considered one of the heaviest albums released by Blue Öyster Cult, its music more akin to heavy metal than the melodic and commercial hard rock of their two previous works. The poor sales of those albums resulted in record label pressure on the band that led to their disbandment in 1986; a subsequent comeback featured only three members of the classic line-up.

The album received some critical acclaim, but was not a commercial success, and Columbia Records ended their contract with Blue Öyster Cult at the completion of the Imaginos Tour. Albert Bouchard, excluded from the recording progress of Imaginos after the initial rejection from Columbia Records, then took legal action against the band and the label to protect his rights as author and producer on the album. Blue Öyster Cult continued to perform and remained a live attraction, but ten years passed before they released an album of new songs.

The concept and the character of Imaginos were originally created by the young Sandy Pearlman for a collection of poems and scripts called The Soft Doctrines of Imaginos (sometimes reported as Immaginos), written in the mid-1960s during his formative years as a student of anthropology and sociology at Stony Brook University, Brandeis University and The New School. Pearlman combined cultural references learned in his studies with elements of gothic literature and science fiction, and created a secret history about the origin of the two world wars. Pearlman himself declared his predilection for the American weird fiction author "H. P. Lovecraft and other writers of that ilk", as well as for books on modern warfare and conspiracies.

Established by 1967 as a critic for the seminal US music magazine Crawdaddy!, Pearlman was also the mentor, manager and producer for the band Soft White Underbelly, which, after various name changes, became Blue Öyster Cult, a term taken from the Imaginos script. The adapted and amended rhymes of Pearlman, along with his friend and colleague Richard Meltzer's arcane writings, were used as lyrics for most of the band's early songs; musician and writer Lenny Kaye recalls in his introduction to the re-mastered edition of their first album that "the band kept a folder full of Meltzer's and Pearlman's word associations in their rehearsal room, and would leaf through it, setting fragments to music". Fragments of the Imaginos script are scattered out-of-context throughout the songs of the first four albums, where the original meanings are lost to listeners unaware of the larger picture. The resulting mystery feeds fan fascination for the music of Blue Öyster Cult, and is responsible for their reputation as "the world's brainiest heavy metal band". Much fan speculation centers around lyrics' relationship to the Imaginos storyline, while Pearlman's deliberate reticence and misleading in revealing his sources only augments the obscurity of the matter. During the band's first period of activity, the theme of the alien conspiracy became more defined and predominant in the mind of its author, to the point that notes on the cover of their 1974 album Secret Treaties referred to the secret history conceived by Pearlman, while its songs "Astronomy" and "Subhuman" contained lyrics fully dedicated to the Imaginos plot.

The band sought to separate creatively from Pearlman in the late 1970s; they avoided his lyrics and concepts and refused to record an album entirely dedicated to Imaginos, but eventually returned to his material for the lyrics of "Shadow of California" (from The Revölution by Night of 1983) and "When the War Comes" (from Club Ninja of 1985). Pearlman and Albert Bouchard hoped to record such an album, and as far back as 1972 had begun to write songs directly inspired by the Imaginos story. Nonetheless, with the exception of the extracts used for song lyrics, the text of The Soft Doctrines of Imaginos remains to this day largely unknown and unpublished.

The commercial success of the single "(Don't Fear) The Reaper" in 1976, and a series of Platinum and Gold discs in the following years, placed pressure on the band as their label, Columbia Records, expected them to repeat these successes. Despite good sales of the album Fire of Unknown Origin and the single "Burnin' for You", in August 1981 the conflicts and the stress accumulated in more than ten years of cohabitation led to the firing of drummer Albert Bouchard, a founding member and an important contributor to the songwriting and sound of the group, allegedly for unstable behavior. The relationship between the former band mates remained tense in the following years. Old feuds resurfaced during a short reunion tour with the original line-up in 1985, with the result that no one in the band accepted Bouchard back in Blue Öyster Cult. However, Bouchard still hoped to be reinstated in the band through his work done for Imaginos.