In agreement with the movies "Highlander II" and "Highlander: The Final Dimension", the series showed that immortals don't need to directly kill another immortal to absorb their Quickening energy and that there is no energy released if there isn't an immortal nearby. When mortals threaten to behead the immortal Fitzcairn, he warns "there will be no Quickening" and that all of his power and "knowledge" will be lost since there is no immortal among them. Series producer Panzer later said, "as long as an immortal is present, he gets the Quickening... if there is no immortal present, then the Quickening just goes to the Source." The Source is never fully explained, but is implied to be an energy well that gives newborn immortals their initial power.