Video Screenshot Termination

Video capture of a regional screenshot (initiated by Command-Shift-5) yields an infinite response: terminated only by powering off my Mac Mini running macOS Monterey V 12.5.1 (21G83). As my attempt was the first in my 12-year experience with recent Apple products, my presumption was that the Escape key would terminate video capture. Wrongoh. What magic key combination WILL terminate video capture with desired file creation? In addition to the frustration attendant in AC power down and restarting, no video file was saved!