Asymmetric chorea unrelated to structural lesions is typically due to systemic etiologies, such as metabolic, autoimmune, or other inflammatory disorders. This is an editorial commenting on a paper by Batot C, Chea M, Zeidan S, et al. Clinical and radiological follow up of Pfizer-BioNTech COVID-19 vaccine-induced hemichorea-hemiballismus. Tremor and Other Hyperkinetic Movements; 2022; 12(1). DOI: https://doi.org/10.5334/tohm.688. A 90-year-old patient is reported who developed hemichorea shortly after his second vaccination against COVID-19. Hypometabolism was noted in the contralateral striatum. This case provides potential insights and raises questions about mechanisms of immune-mediated hemichorea.