1ES 1927+654\: the first optically-identified changing-look

The physical process responsible for the socalled optical changinglook AGN,i.e. sources in which the broad lines produced by material surrounding the SMBHappear or disappear, is still very debated. We recently caught one of these rareobjects in the act of developing broad lines. This is the first time a source isobserved during the changinglook phase. The XMMNewton/NuSTAR DDT we triggeredhas shown an extremely peculiar supersoft Xray spectrum, with only a fewphotons above 2 keV. We propose here two 42 ks XMMNewton observations of thisunique source to monitor its spectral behaviour, and in particular thereappearance of the hard component. We will also study its outflow and possiblydetect a K line. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]