Audiences may devour the fictional Hollywood romances that fill theaters every week, but unless they’re familiar with the title characters of Chris & Don: A Love Story, it may initially be hard for them to care about this true one. Regardless of whether you recognize the names of Christopher Isherwood, the English writer whose accounts of his time in Berlin became the basis for the musical Cabaret, or Don Bachardy, a Los Angeles–born portrait artist, however, Guido Santi and Tina Mascara’s masterful documentary draws you into the men’s lives like a star-studded bedtime tale.

The film begins with the 74-year-old Bachardy pulling out his dead lover’s diary, which he said he began reading as soon as Isherwood passed away in 1986. Some passages from the journal, narrated by Michael York, give insight of Isherwood’s feelings regarding his relationship with Don, who was 16 years old and 30 years Isherwood’s junior when they met. (If the numbers don’t jar you, a photo in which Isherwood could easily be mistaken for Bachardy’s father will.) Mostly, though, the recollections come directly from Bachardy, still sprightly, physically fit, and full of charm as he talks about their upbringing, their epic and unapologetic affair during an era when many homosexuals wouldn’t think of coming out, and their mutual fascination with Hollywood.

Like the families in the docs Capturing the Friedmans and Surfwise, Isherwood and Bachardy incessantly chronicled their lives. Grainy home videos, photos, and countless drawings re-create a relationship that spanned three decades and featured all the ups and downs of a typical domestic drama. Already successful when he got involved with Bachardy, Isherwood helped the young man figure out his path and develop his talent as a painter. Bachardy, as green as a Los Angeles boy could likely be, was both fascinated and intimated by his boyfriend’s celeb-swimming lifestyle. Once Bachardy came into his own as an artist and a man, he longed for sexual freedom, leveraging Isherwood’s own devil-may-care youth to give Bachardy permission to spend a few years “mousing.” Bachardy considered leaving during this time, but ultimately stayed, nursing Isherwood through the prostate cancer that took his life.

The directors don’t deliver this story dryly, however. One of the film’s highlights is the adorable animated sequences of the drawings the couple used to represent themselves in notes to one another: Isherwood is represented as a gentle horse, Bachardy his affectionate kitty. Bachardy’s vivid memory and way with words—you don’t hear many people say “putting on the dog” anymore—make him a delightful storyteller, particularly when he’s talking about how he fell in love not just with Isherwood but Hollywood as well: Born to a mother who would certainly be a People subscriber today, Bachardy recalls that his first film was Joan Crawford’s The Shining Hour—at age 4!—and that he’d take himself to the movies every week. Of course, Bachardy’s last years with Isherwood weren’t so joyful; the stark portraits he drew of his dying partner, often several a day every day, convey more sorrow than his words ever could. Chris & Don tells the story of a love too rich to make up, and a line from Isherwood’s diary suggests he knew that all along: “Why invent,” he wrote, “when life is so prodigious?”