What constitutes a “threatening tone of voice”? There is currently little research exploring how listeners infer threat, or the intention to cause harm, from speakers’ voices. Here, we investigated the influence of key linguistic variables on these evaluations (Study 1). Results showed a trend for voices perceived to be lower in pitch, particularly those of male speakers, to be evaluated as sounding more threatening and conveying greater intent to harm. We next investigated the evaluation of multimodal stimuli comprising voices and faces varying in perceived dominance (Study 2). Visual information about the speaker’s face had a significant effect on threat and intent ratings. In both experiments, we observed a relatively low level of agreement among individual listeners’ evaluations, emphasising idiosyncrasy in the ways in which threat and intent-to-harm are perceived. This research provides a basis for the perceptual experience of a “threatening tone of voice,” along with an exploration of vocal and facial cue integration in social evaluation.