Official Release #61. The date is October 28, 1968. The Mothers of Invention are playing the Royal Festival Hall in London. Frank Zappa has booked 14 musicians from the BBC Symphony Orchestra to accompany them during the first part of the show. He had been writing chamber music pieces in the hotel rooms he visited and wanted to try them out. He strung them together by devising a psychodrama he called "Progress?" This was meant (and indeed turned out) to be a one-time performance, so he made sure to record it. He released the whole thing as Ahead of Their Time 25 years later. The first half of the disc is comprised of the "play."
From the perplexing Germanic interlude of the opener, "Didja Get Any Onya?" to the complex xylophone changes of "The Eric Dolphy Memorial Barbecue," Zappa combines avant garde music, jazz, R&B, novelty elements, and plenty of flippant rock attitude. Interestingly, there are some straight-up rock tracks too, such as the interpretation of Little Richard's "Directly From My Heart To You," and the guitar-led attack of "My Guitar Wants to Kill Your Mama," balancing highbrow conceptualism with unpretentious directness in Zappa's inimitable fashion.