As Styx finally achieved a long-hoped-for measure of success, they did a rare thing in rock music back then: They looked inward. The Grand Illusion, released on July 7, 1977, talked with bold frankness about the trappings of celebrity, the uncertainty of their new position and the worries each member had about the way fame might change him.

These sweeping themes grew out of the title track, brought to Styx by Dennis DeYoung and appropriately placed as the album-opening song.

"It spoke to all of us and what we were experiencing as members of the same band, as our popularity grew and we started to make some money," Tommy Shaw told the Daily Herald. "We were a very tight group musically at that time, and it was all for one and one for all – this wonderful moment in the life of any band. So we all began to pour our hearts into it like one big 'amen!'"

Shaw has called this era, which also included the 1978 follow-up LP Pieces of Eight, "the prime season of innocence." He'd joined the year before, becoming a key creative element on 1976's transitional Crystal Ball, but The Grand Illusion – featuring his Top 30 hit "Fooling Yourself (The Angry Young Man)" – was where Shaw completely integrated with the group's larger dynamic.

"We went on the road and toured, and it really took that time for us to become a band with Tommy. We became writers together and The Grand Illusion is the outcome," DeYoung told Classic Rock Revisited. "I was the theme guy in Styx and I had come up with the theme. I got everyone together and I said, 'Look, in the last year we’ve made more money than we ever thought we would make in our entire lives. How has it affected us?' I know how it had affected me. We set on a course of trying to make a loosely thematic album based on success, failure and money."

Even before DeYoung's "Come Sail Away" became their second Top 10 single, there was the sense that The Grand Illusion represented a creative – and commercial – breakthrough. Album sales certainly confirmed the latter, as the project became the first of four straight multi-platinum releases for Styx.

Listen to Styx Perform 'Fooling Yourself'

"I think we all knew that this was our best work to that point," James "J.Y." Young told Ultimate Classic Rock. "There was a very cohesive thing from the title of the record. There was a resonance there of a concept album or whatever, so I think we felt like we really had captured something."

The success-hungry alienation of "Fooling Yourself" and "Come Sail Away," with its dark, underlying theme about pots of gold never found, gave way to sharply drawn deeper cuts like "Man in the Wilderness." Composed on the spot by Shaw after Styx played an eye-opening early support gig for Kansas before thousands of fans in Detroit, it outlined the range of emotions in this fast-moving time.

"To go that big opened up all kinds of ideas in my mind, and the next time I was alone with my acoustic, the song more or less unfolded itself. The lyrics were there in rough form right away," Shaw told the Daily Herald. "Think about it: To go from playing in a bowling alley lounge to the kinds of venues we were beginning to play on a regular basis, and being away from home all the time, it was strange at first to be standing out there getting that kind of response from so many people who didn't really know me or how I was feeling at the time."

Elsewhere, the theme is completed by "Miss America," Young's hard-eyed, riffy indictment of superficiality; and "Castle Walls," an elliptical examination of the barriers that surround us from DeYoung. Styx's newfound ability to maintain the delicate balance between those competing musical impulses is what made The Grand Illusion such a breakthrough moment.

"The beauty of the creative team back then is that we were different," Young told Ultimate Classic Rock. "We were all different individuals and so everything that creatively came out was really held to very high standards from a dozen different angles, as opposed to everyone playing the same thing. There was lots of layers to what we did, both musically and arrangement-wise – and the amazing thing is that the work really seems to have wonderfully withstood the test of time."

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