<p>Instantaneous rigor, historically referred to as cadaveric spasm, remains a controversial concept in forensic pathology with divergent interpretations. Despite skepticism regarding its status as a distinct entity, apparent immediate postmortem fixation—particularly of the hands—continues to be reported. We describe a witnessed suicidal railway fatality in a 38-year-old female who exhibited unusual limb postures suggestive of instantaneous rigor. Detailed scene reconstruction and autopsy revealed heterogeneous limb positioning: some postures were attributable to biomechanical support, whereas others, particularly involving the hands, were not readily explained by environmental factors, object retention, or conventional postmortem changes. These findings may be better interpreted as reflecting terminal neuromuscular activity during a brief agonal phase, followed by stabilization of the resulting posture by early rigor mortis. A comparable suicidal hanging case demonstrated similar hand postures, providing additional observational support for this proposed interpretation. Overall, these observations are consistent with a hypothesis that apparent instantaneous fixation may represent a continuum of terminal neuromuscular phenomena rather than a distinct postmortem entity. Careful correlation of scene findings with autopsy features remains essential when interpreting such unusual postmortem postures. Although these observations are hypothesis-generating, they highlight the importance of distinguishing terminal agonal neuromuscular activity from postures traditionally attributed to cadaveric spasm during medico-legal interpretation.</p>