Thunderbolt Jim Lang, wanted on robbery and murder charges, ventures out with his girl, "Ritzy", to a Harlem nightclub, where she informs him that she is going straight. During a raid on the club, Thunderbolt escapes. His gang shadows Ritzy and reports that she is living with Mrs. Moran, whose son, Bob, a bank clerk, is in love with Ritzy. Fearing for Bob's safety, Ritzy engineers a police trap for Thunderbolt; he escapes but is later captured, tried, and sentenced to be executed at Sing Sing. From the death house, he successfully plots to frame Bob in a bank robbery and killing. Bob is placed in the facing cell, and guards frustrate Thunderbolt's attempts to get to his rival. When Ritzy marries Bob in the death house, Thunderbolt confesses his part in Bob's conviction. He plots to kill the boy on the night of his execution, but instead at the last minute his hand falls on Bob's shoulder in a gesture of friendship.
Thunderbolt was Sternberg’s first film using synchronized sound technology. Two versions of the film were produced, including a silent version for theatres that had yet to be adapted to sound. The technical innovation of synchronized dialogue into film raised concerns among directors as to its potential influence on the visual techniques available to directors. Internationally, filmmakers such as Eisenstein, Pudovkin, Hitchcock and Vertov wished to avoid oppressive forms of ”theatrically-influenced dialogue” even as audiences clamored for the novelty of naturalistic speech. Sternberg welcomed sound as a means to achieve complete control over his picture - "no longer at the mercy of movie house organists" - and eschewing any "atmospheric" or background music. Thunderbolt used source music that arose directly from the mise en scène. Sternberg experimented with asynchronous sound effects which served to augment or supplement the visual effects, or as he framed the process, “To be correctly and effectively used, sound had to bring to the image a quality other than what the lens included, a quality out of the range of the image. Sound had to counterpoint or compensate the image, add to it – not subtract from it.” Throughout Thunderbolt, Sternberg “uses sound to paint audio images” through “complementary and contrapuntal juxtaposition.” Rather than the external and complementary musical accompaniment of silent films, Sternberg’s scores arise organically with the mise-en-scène and form a key component of the film. The music off-screen does not recede in deference to the on-screen dialogue, but competes with it. Off-screen, voices comment on the visual action, but are not identified visually until later in the film sequence, contributing to an “unrealistic cadence” that characterizes the film’s dialogue. Film historian Andrew Sarris describes it as "a startling experiment... his use of sound and music for mood effects, and the very unreality of his style seems to justify the unusual density of his sound track." Sternberg also uses sound expressionistically, such as the erratic start-stop of a sewing machine or the “sinister” squeaking of a dog’s ball toy, squeezed by the condemned criminal in the hours before his death.
Reception
writing for The New York Times described the screenplay as “a musical comedy plot striving to masquerade as drama.” Film critic Andrew Sarris would echo that assessment in 1966, writing “Thunderbolt is, in some respects, as much a musical as a melodrama.” Film historian Janet Bergstrom points out that “reviewers were relieved that Sternberg had returned to the gangster genre he had invented and made popular", as in this review entitled “Thunderbolt Registers Hit” from Norbert Lusk of the Los Angeles Times : German filmmaker Ludwig Berger contacted Sternberg via telegram with fulsome praise: "I saw your film Thunderbolt and congratulate you with all my heart. It is the first fully realized and artistically accomplished Sound film. Bravo!"
