Tony Curtis stars as Johnny Dark, a moody automobile designer. Rejected by a major auto firm because of his "radical" notions, Johnny sets out to prove the efficiency of his cars on the racetrack. He is aided and abetted by pretty Piper Laurie and less pretty Paul Kelly, while motor mogul Sidney Blackmer fumes and fusses until he realizes that Johnny's designs will save his company. Most of the film is devoted to a marathon race, pitting Johnny against his friendly enemy Don Taylor. Johnny Dark is a must for racing buffs, as well as a prime example of Tony Curtis in his beefcake period.
~ Hal Erickson, All Movie Guide