Kirk Honeycutt of "The Hollywood Reporter" described it as an intriguing and smart exploration of vigilantism that could become a cult film. Roger Ebert of the "Chicago Sun-Times" rated it 3.5/4 stars and wrote, "In a genre populated with formulas and dreck, "Boy Wonder" is an ambitious exception, well-made, drawing us in." Jeannette Catsoulis of "The New York Times" wrote, "Despite its aura of rebellious cool, "Boy Wonder" is as frigid and empty as Sean’s vengeful heart." J. R. Jones of the "Chicago Reader" wrote, "Visually and rhetorically, this is indistinguishable from a network cop show."