Armed with his trusty Appleton's Guide, Michael Portillo reaches San Francisco, where he boards one of the city's iconic cable cars. Behind the scenes in the engineering powerhouse, he uncovers the street cars' secret to scaling the city's famously steep hills. In the Presidio neighbourhood, a leading publisher introduces Michael to San Francisco's long tradition of fine printing and book-making. Michael takes the opportunity to have his own treasured book appraised.

Hitching a ride on a hippy 'love bus' to the heart of the city's gay district, Michael traces the roots of the city's LGBTQ scene back to the era of the gold rush and meets the Sisters of Perpetual Indulgence. At Fisherman's Wharf, Michael samples a local seafood speciality brought to the city by Italian immigrants. Across the bay at Sausalito, he boards a schooner to hear the story of Matthew Turner, the most prolific shipbuilder of his time. In Chinatown, Michael hears about the huge contribution Chinese immigrants made to the Californian economy, both as miners and in building the transcontinental railroad. He discovers an entrepreneurial community who overcame discrimination and finds that fortune favours the brave when he learns to create an iconic Chinese treat.

Intrigued by a reference in his guidebook, Michael visits the Sutro Baths, where he learns the story behind an ugly 19th-century incident of racial discrimination, which prompted an African American to sue one of the richest white men in the state. A trip out into the Bay with the San Francisco Police Department's marine unit, established in 1864, shows Michael how the force continues to keep the waters safe.