"Baby Rocket" is the name of a child who, in 1966, was abandoned by her suicidal mother and later found by a policeman in the seat of a children's rocket ride on Cape Canaveral. The novel is the story of this child's (Clementine Dance) adulthood discovery of an abandonment she does not remember, and how she comes to terms with it and her past.

Upon her father's sudden death in Santa Monica during the summer of 1998, Clementine "Lem" Dance finds a file about a "Baby Rocket" on his computer. The file suggests she is Baby Rocket but she's never heard the name; and her late father, a former NASA employee, James Walter Dance, Jr., had been prone to romantic white lies - he claimed he once met Marilyn Monroe, for example. The file on "Baby Rocket" seems crazy and yet all too real: it contains Lem's birth certificate, a document which shows that her father was not her biological but rather her adoptive father and emails that show he'd been in contact with her birth mother's surviving family - as if he'd been on the verge of telling the truth.

These upheavals force Lem to retrace her parents' lives and to re-examine her own; to get in touch with her mother's family; and, above all, to try to remember Baby Rocket. Before her discovery, she'd felt she knew herself. Afterwards, even her own "jet-age" nickname "Lem" - or LEM, for the Lunar Excursion Module - seems like a bad joke: once a symbol of hopeful futurity for her, given that she shares her name with an historical emblem of technological progress, the name only serves to remind her of a past she doesn't recognize. Such a journey takes her across the landscape of late 20th-century America, both geographically - from California to Cape Canaveral - and in time, in memory. As she pieces together the forgotten "Baby Rocket," she re-inhabits the culture and dreams of the 1950s and 1960s, a time, a place and a vision that shaped her parents and herself.