Roots: In his foreword, Graham Joyce compares the Doctor to Tom Bombadil from The Lord of the Rings. There are references to Jefferson Airplane, the Grateful Dead, Janis Joplin, Santana, the Quicksilver Messenger Service, Timothy Leary, Ken Kesey's Merry Pranksters, Big Bother and the Holding Company, the Twilight Zone, President Kennedy, Senator Kennedy, the Rolling Stones 19th Nervous Breakdown, Country Joe and the Fish's I Feel Like I'm Fixin to Die, the Beatles, Ambrose Bierce, Jack London, Dr. Strange, Steve Ditko, Jim Morrison, Timothy Leary, John Lennon, Snow White, Bob Dylan, Yoko Ono, James Bond, and Goldfinger.
Dialogue Triumphs: 'If there's one things I've learned on my travels, it's that, for all its horrors, the universe tends towards good. In the middle of a moment, it's easy to see darkness, and to give in to the blackest despair. But across the scope of centuries, the view reveals a path that always encounters valleys but continues ever higher, that never stops rising.'
Continuity: The Colour-Beast is one of a race of beings so powerful that their true nature is beyond human comprehension. They can move throughout space and time at will and can alter perception at the most fundamental level. Their essence is capable of affecting the human mind in such a way that it transforms humans into hybrids of the creatures. Humans cannot normally see the creatures unless their minds have altered by hallucinogenic drugs such as LSD. The Combine captured a Colour-Beast that became stranded on Earth and extracted essence from it, which they included in the Blue Moonbeam pills.
The Combine is a stupid hippie-name for the group of people that really run America.
The Doctor is still wearing his stove-pipe hat (The Power of the Daleks). He also dons his long black cloak. He synthesizes a substance that mimics the effects of LSD without any of the dangerous effects. The Fourth Doctor later returns to America to rescue Jessica Summer Williamy from being executed by agents of the Combine, presumably dropping her off a year later following the publication of Jack Stimson's exposé The Secret Government an investigation of the corruption at the heart of America.
Ben doesn't really believe in conspiracies.
Links: In its attempts to communicate with the Doctor, the Colour-Beast sends images of the head of a Cyberman (The Tenth Planet), a Menoptra (The Web Planet), and components of WOTAN (The War Machines).
Location: Haight-Ashbury, San Francisco, January 1967, and an undisclosed location somewhere in America, towards the end of the twentieth century.
Unrecorded Adventures: The Doctor has met the Beatles, and claims to have been responsible for suggesting to George Harrison that he visit the Maharishi Mahesh Yogi for spiritual guidance.
The Bottom Line: Placing the most anarchic Doctor in the midst of Haight-Ashbury in the middle of the Summer of Love is an inspired idea, and whilst showing the Doctor and his companions entirely from the point of view of a supporting character is hardly novel, Chadbourne's characterisation of Summer is so effective that it works perfectly. All-in-all, rather charming.