Vehicle 19 is best when it’s silent. Mukunda Michael Dewil’s film has the makings of a taut little thriller, but the writer-director has the twin disadvantages of needing to include dialogue and to rely on the services of Paul Walker to embody his protagonist. The film follows American Michael Woods (Walker) as he arrives in Johannesburg, South Africa, to reunite with his ex-wife after being released from prison and jumping parole. But when he’s accidentally given the keys to the wrong rental car, he finds himself amid a scandal which involves a sex-trafficking ring and implicates the chief of police, who suddenly wants him dead. As Michael drives through the urban streets, dodging police vehicles, the film largely confines its setting to his car, allowing the sinister world outside to materialize in evocative snatches through the window. Unfortunately, Dewil too often fills in the silences of this largely one-man show by having Michael talk to himself, reiterating obvious bits of narrative business, all of which culminates in his spelling out for the audience how this mission represents his chance at redemption. It’s all relayed via Walker’s sledgehammer delivery, which never admits an ounce of subtlety or nuance.