An album cover is a window to its contents. From a marketing perspective, a disk cover or a vinyl sleeve that stands out from the shelf is an advantage. For the artists, it is the visual representation of their work.

However, some artists slip a message or a detail not directly available at first glance. Here are four classic album covers with hidden details you might find after looking again.

"Ram" by Paul McCartney and Linda McCartney (1971)

"Ram" marks Paul McCartney's second studio album after The Beatles' breakup. In this album, Macca worked with his wife Linda and drummer Denny Seiwell. The three would later found the rock band Paul McCartney and Wings, with Moody Blues' Denny Laine.

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The album cover has a very 70s background with Paul McCartney petting the titular ram. However, look closely at the red edge of the cover, and you'll find L.I.L.Y. written. It stands for "Linda I Love You."

"Retro Active" by Def Leppard (1993)

The 1993 compilation by the British hard rock act Def Leppard has a glaring multi-layered album cover art. Its design, by Nels Israelson and Hugh Syme, features an old-timey photograph of a woman starting back through the reflection of a mirror. Looking at the illuminated part of the cover again creates a skull. The actual and reflected image of the woman's head forms the eyes while other accessories form the nose and the teeth.

Def Leppard's
(Photo: Wikimedia Commons)

It was a hard-fought Def Leppard project, which closed the door to their Steve Clark era. They first thought of the concept for "Retro Active" shortly after the success of their hit "Two Steps Behind."

"Mirage" by Fleetwood Mac (1982)

Transatlantic rock legend Fleetwood Mac released "Mirage" in June 1982 to commercial and critical success. It spawned the hits "Love In Store," "Can't Go Back," and "Gypsy. A deluxe edition of the album was released in September 2016. It includes the original tracks and the other songs recorded but didn't make the final setlist.

In its full album cover, the members pose against a pitch-black background. In the right-side end, Stevie Nicks and Lindsey Buckingham holding hands, as if in a dance. The "Mirage" in their album cover is between their interlocked hands, which looks like there's a face in it.

"Santana" by Santana

The Latin rock band led by guitar legend Carlos Santana released this 1969 album. Even with more than half of its contents having no lyrics, it was still a beloved rock album. Although, it was widely panned during its first release. Langdon Winner, writing for Rolling Stone, called the album "a speed freak's delight" and "a masterpiece of hollow techniques."

Santana's Self-titled 1969 Album
(Photo: Wikimedia Commons)

Its cover art, at first glance, looks like a lion with the band logo on the right. Look closer, and you'd realize that it is actually a group of human faces. These faces are arranged in such a way that they form a lion. Look closely at the lion's maw, and its upper row of teeth is actually a necklace worn by a woman. It goes down, with the lion's jaw being the woman's hula skirt.