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We present the drastic transformation of the X-ray properties of the activegalactic nucleus 1ES 1927+654, following a changing-look event. After theoptical/UV outburst the power-law component, produced in the X-ray corona,disappeared, and the spectrum of 1ES 1927+65 instead became dominated by ablackbody component ($kT\sim 80-120$ eV). This implies that the X-ray corona,ubiquitously found in AGN, was destroyed in the event. Our dense $\sim 450$ daylong X-ray monitoring shows that the source is extremely variable in the X-rayband. On long time scales the source varies up to $\sim 4$ dex in $\sim 100$days, while on short timescales up to $\sim2$ dex in $\sim 8$ hours. Theluminosity of the source is found to first show a strong dip down to $\sim10^{40}\rm\,erg\,s^{-1}$, and then a constant increase in luminosity to levelsexceeding the pre-outburst level $\gtrsim $300 days after the optical eventdetection, rising up asymptotically to $\sim 2\times10^{44}\rm\,erg\,s^{-1}$.As the X-ray luminosity of the source increases, the X-ray corona is recreated,and a very steep power-law component ($\Gamma\simeq 3$) reappears, anddominates the emission for 0.3-2 keV luminosities $\gtrsim10^{43.7}\rm\,erg\,s^{-1}$, $\sim 300$ days after the beginning of the event.We discuss possible origins of this event, and speculate that our observationscould be explained by the interaction between the accretion flow and debrisfrom a tidally disrupted star. Our results show that changing-look events canbe associated with dramatic and rapid transformations of the innermost regionsof accreting SMBHs.

The destruction and recreation of the X-ray corona in a changing-look Active Galactic Nucleus