Creutzfeldt-Jakob disease (CJD) is a rapidly progressive neurodegenerative disorder that encompasses symptoms such as dementia, myoclonus, visual or cerebellar impairment, pyramidal and extrapyramidal motor deficits, akinetic mutism and ataxia. The term “alien limb phenomenon” (ALP) describes involuntary motor activity in one limb while simultaneously experiencing a sense of estrangement from that same limb. ALP is a typical sign of corticobasal syndrome and has also been described in CJD. This clinical vignette presents the rapid clinical progression of a patient with left ALP and ideomotor apraxia as early symptoms of CJD. Three weeks prior to admission, an independent, 83-year-old, right-handed patient with no relevant medical history had a feeling of estrangement of his left hand, accompanied by a progressive loss of voluntary motor function. Within two weeks, he was unable to ride his bicycle and needed help with activities such as buttoning his shirt. Over time, he reported uncontrolled movements of his left hand that caused repeated dropping of objects. An outpatient magnetic resonance imaging (MRI) of the brain did not reveal any significant findings, specifically no stroke and focal brain atrophy. On admission on December 20, 2021, the patient presented with dystonic posturing, occasional myoclonus and ataxia mainly affecting the left arm (Video 1, Segment 1). Other neurological signs like paresis, rigidity, tremor or aphasia were not present.