Different mechanisms of block of impulse propagation in several re-entrant circuits resulted in a major discordance between the "echo-zone" and the "tachycardia-zone" in a patient with intermittent Wolff-Parkinson-White syndrome, dual atrioventricular nodal pathways, and bundle branch re-entry. This case illustrates the delicate balance in electrophysiological properties required between the tissues incorporated in a re-entrant circuit to initiate and sustain the arrhythmia. It also shows how the presence of several reentrant pathways can lead to refractoriness in the circuit responsible for the circus movement tachycardia.