| Alois |
Alzheimer | German psychiatrist and neurologist |
| Frau |
Auguste Deter | First documented Alzheimer's patient |
| David |
Bowie | English singer-songwriter and actor |
| Mr. |
Byers | Ruth's third-grade teacher |
| Mr. |
Deforest | Ruth's neighbor |
| Chris |
Evert | American former tennis player |
| Art |
Garfunkel | American singer and actor |
| Maxine |
Grooms | Doctor and Ruth's friend |
| Ernest |
Hemingway | American novelist and journalist |
| Katharine |
Hepburn | American actress |
| Lou |
Jr. | One of Bonnie's boss's children |
| Robert |
Kearns | American engineer |
| Dean |
Levin | University dean who had an affair with Howard |
| Blake |
Lively | American actress |
| Dr. |
Lung | Howard's doctor |
| Mrs. |
Lung | Wife of Dr. Lung |
| King |
Midas | Legendary king of Phrygia |
| Alanis |
Morissette | Canadian-American singer and musician |
| William |
Mulholland | Irish-American civil engineer |
| Dr. |
Nazaryan | Ruth's acquaintance |
| Jack |
Nicholson | American actor and filmmaker |
| Brad |
Pitt | American actor and film producer |
| Ron |
Popeil | American inventor |
| Smokey |
Robinson | American singer-songwriter and producer |
| Lou |
Sr. | Ralph and Lou Jr.'s father |
| Jimmy |
Stewart | American actor |
| Shirley |
Temple | American actress and diplomat |
| John |
Travolta | American actor |
| Oprah |
Winfrey | American host and TV producer |
| Howard |
Young | Beloved history professor whose memory is fading due to Alzheimer's disease |
| Adam |
| Ruth's acquaintance |
| Annie |
| Ruth's mother |
| Bella |
| Deb's daughter |
| Bill |
| Pet store owner |
| Bonnie |
| Ruth's childhood best friend |
| Carl |
| Ruth's old friend |
| Charles |
| Bonnie's friend |
| Confucius |
| Chinese philosopher |
| David |
| Lawyer |
| Davy |
| Franklin's two-year-old son |
| Deb |
| Ruth's high school friend |
| Fluffy |
| Cat |
| Franklin |
| Mechanic |
| Harley-Davidson |
| American motorcycle manufacturer |
| Harry |
| One of Howard Young's students |
| Jake |
| One of Howard's tallest students |
| Jared |
| Sushi chef |
| Jemima |
| Neighbor's aunt |
| Joan |
| Theo's friend |
| Joel |
| Ruth's ex-fiancé |
| John |
| Ruth's uncle |
| Joseph |
| Howard's acquaintance |
| Katrina |
| One of Regina's children |
| Kevin |
| Baby boy Maxine is adopting |
| Kristin |
| Joel's girlfriend |
| Layla |
| Waitress |
| Linus |
| Ruth's brother |
| Liza |
| John's girlfriend |
| Noah |
| Pygmy goat |
| Patrick |
| Policeman |
| Phyllis |
| Kearns's wife |
| Ralph |
| One of Bonnie's boss's children |
| Reggie |
| Ruth's old friend |
| Regina |
| Ruth's acquaintance |
| Rita |
| Linus's girlfriend |
| Ruth |
| The protagonist and narrator |
| Sam |
| Ruth's friend |
| Sandy |
| One of Regina's children |
| Theo |
| Howard Young's teaching assistant |
| Vince |
| Bonnie's boyfriend |
| William |
| Deb's high school boyfriend |
