The title comes from an old man Régnier overheard in a Belleville café in the 1990s who told two younger men sharing a joint that he didn’t need it because he was already “dosed,” meaning naturally balanced (“I’m comfortable in my chair”). Régnier, who was there to buy hashish, has never felt that way. His chapters in this alternating-author memoir cover his first LSD trip in the Scottish Highlands in 1970, the Paris communes of the early 70s, consuming hash cookies in Morocco, a harrowing afternoon on the Parkinson’s drug Artane at age 17, cocaine use in the film business, and years spent on antidepressants. Browning, who is nearly a decade younger, grew up with a hard-drinking mother and a bipolar father and initially passed on weed in high school. She came to drugs late, taking LSD twice with Régnier in her 50s and becoming their household’s expert baker of cannabis cookies. The couple’s shared episodes include a bad trip on capsules bought in Amsterdam and a strange visit to two Montreal musicians in recovery. Along the way, both write candidly and humorously about aging, illness, music, their parents, and their late-life romance. Reading about someone else’s drug trips can be boring, but this book mostly avoids that trap thanks to its fleet pacing and the authors’ erudition. Régnier draws on a deep well of French Boomer experiences and touchpoints, and both authors bring in a wide range of literary references: from Balzac and Oliver Sacks to Zora Neale Hurston and George Sand. Chapters often answer the ones preceding them, making the book feel like an exchange of letters; the approach endearingly highlights the ways in which the two argue, tease, and take care of each other. (Their back-to-back accounts of the Dutch bad trip are a highlight.) A few chapters wander, and certain theoretical asides can feel slight, but the book succeeds as a compelling portrait of two very different people reflecting on times spent together and apart.