Arlo Harkin is a twelve-year-old autistic boy living on a farm in The '50s with his grandfather and his uncle Louie. One day, he falls out of an oak tree and hits his head on a rock. When he wakes up, he discovers that he now has synesthesia, that he can perceive tiny details in his environnment, and that he seems to have precognitive abilities. He sets out on a journey to try to understand and learn how to use his gifts.
The Savant contains examples of:
- 6 Is 9: Arlo and Louie lose the first ten dollars they bet at the Kentucky Derby because Arlo accidentally reversed a six for a nine in his head.
- The Alcoholic: Louie has been a heavy drinker ever since he got home from the war.
- The Alleged Car: Arlo and Louie drive to Kentucky in Louie's 1940 Ford, but it keeps breaking down along the way, and they end up spending most of the $1,000 they brought on repairs. Louie trades it for a brand-new Ford Fairlane 500 Convertible as soon as he can afford to.
- Arc Words: Arlo sees an ad in the paper for the book Think and Grow Rich. He never buys the book, but he often thinks of the title, first as a description of his goals, then as something he's moved past.
- Book Ends: Both the first and the last sentences of the book have Arlo at the top of the oak tree, where he has an "eternal view of the world."
- Briefcase Full of Money: How Arlo and Louie keep the money they win at the local races. Louie wants to bring it all to Kentucky, but Arlo insists that they leave most of it at the bank because he's afraid Louie will spend it all on alcohol and girls.
- Cement Shoes: Bucketeer Mario Portalini owes money to the Mafia. He's threatened with being tossed into the Hudson River in cement boots.
- Child Prodigy: Arlo becomes one after his head injury. Before, he was thought to be a moron.
- Contemplation Location: Arlo uses his grandfather's newspaper room for this purpose.
- Distant Epilogue: Arlo is writing the book as a ninety-year-old, shortly before his wife's death. He predicts his own death in 13 years.
- Domestic Abuse: Arlo's mother's second husband turned out to be violent and controlling. He forced her to abandon Arlo because he didn't want to be responsible for an idiot child, even though she felt horrible about it.
- Five-Finger Discount: Arlo is targeted by a pickpocket while he's traveling across the Mediterranean in a cargo boat. He manages to kick the man overboard. Arlo isn't worried about him, since there are fishing boats nearby that could rescue him.
- Florence Nightingale Effect: Louie marries Sue, a counselor at Hope Clinic, where Arlo persuaded him to go into rehab for his addictions.
- Fourth-Date Marriage: Arlo's parents met while walking in a park. They were married in Las Vegas the next day. Shortly thereafter, his father was shipped off to fight in World War II and was killed months before Arlo's birth, leaving his mother a widow at seventeen.
- The Gambling Addict: Louie tends to take large amounts of money from his and Arlo's account to spend on gambling.
- Healthcare Motivation: Arlo's mother steals money from his account to pay the medical bills of her younger son, who was badly injured in the same car accident that killed her second husband.
- Innocent Prodigy: Arlo's sheltered upbringing and poor understanding of other people cause him to get ripped off a lot.
- The Klutz: Arlo wonders what he'll do for a living when he grows up, as he's too unsteady on his feet to be a firefighter or a tractor driver.
- Literal-Minded: Arlo gets confused when people tell jokes or use expressions.
- Little Stowaway: Arlo hides in the storage room of a luxury boat to travel from Leros to Patmos.
- Lives in a Van: When Arlo and Louie arrive in Kentucky, they only have $25 left. They sleep in Louie's car because they can't afford a hotel room.
- Minor Living Alone: After Arlo persuades Louie to go to rehab, he lives alone in their penthouse.
- Motif: The oak tree Arlo falls out of. It shows up often in his thoughts, symbolizing his future and well-being. When he's doing well, he imagines the tree growing stronger; when he's taken advantage of, he imagines buzzards destroying the tree. He even names the company he founds Tumbling Oaks after his fall. However, he's also scared of the tree, as he associates it with being injured. When he returns home from his journey, he climbs the tree again to overcome his fear.
- Multiple-Choice Future: Arlo sees the future as colored rivers flowing out from people. People could end up in any river depending on the choices they make.
- Parental Abandonment: Arlo's mother and her new husband moved to San Diego without Arlo when he was five.
- Professional Gambler: Snodgrass and Minx, two men who bet on horse races and rob Arlo because he's better at it than they are. Arlo gets his revenge by tricking them into betting all their money on a horse that will lose. The shock of it eventually causes Snodgrass to go straight, but Minx continues on his destructive path.
- Really 17 Years Old: Louie lied about his age so he could join the marines at age seventeen.
- Real Men Take It Black: Arlo likes his coffee black, not because he wants to seem tough, but because cream and sugar disguise the subtle tastes of nuts and berries.
- Sensory Overload: At the Kentucky Derby, Arlo is overwhelmed by all the flashes of colors and concentrates on the asphalt instead. He still feels dizzy and disoriented afterwards.
- Shell-Shocked Veteran: Louie deals with stress by getting drunk and stomping around the backyard screaming about Iwo Jima and cursing the Japs.
- Tap on the Head: Shortly before Arlo and Louie leave Kentucky, muggers knock Louie unconscious with a club and take most of the money they have on hand. Luckily they've already sent most of their winnings back to California, and they still have some money the robbers didn't find.
- Technically a Smile: Arlo notes that the mobster Al has a very threatening smile. He tries to learn the expression himself in case it comes in handy.
- Teen Genius: Arlo turns thirteen while he and Louie are on the way home from Kentucky.
- Trapped by Gambling Debts: Louie ends up in debt to the Mafia this way. He empties his and Arlo's partnership account and still has to beg Arlo for more money.
- Trash of the Titans: Arlo's grandfather is a hoarder. On one side of the house, he keeps things like rusty washing machines and old broken-down cars. He also uses Arlo's father's old bedroom solely for storing the daily newspaper, which he doesn't throw away.
- The Un-Smile: Arlo hires the retired actress Maria to teach him to act normal. He isn't very good at it at first - all his expressions are so exaggerated that they look creepy.
- You Called Me "X"; It Must Be Serious: Louie usually calls Arlo "Kid," so Arlo is surprised when he uses his actual name.
