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Young double star V1318 Cyg, which is associated with a small isolatedstar-forming region around HAeBe star BD+40o4124, has very unusual photometricand spectral behavior. We present results of photometric and spectroscopicobservations in the optical range. We carried out BVRI CCD photometricobservations of V1318 Cyg from 2015 Sept. to 2017 July. For the same period weacquired medium- and low-resolution spectra. Observations were performed withthe 2.6 m telescope. We analyze the historical light curve for V1318 Cyg anddemonstrate that the southern component, V1318 Cyg S, after being rather brightin the 1970s (V$\approx$14 mag) started to lower its brightness and in 1990became practically invisible in the optical. After its reappearance in thesecond half of the 1990s the star started to become very slowly brighter.Between 2006 and 2010 V1318 Cyg S started brightening more quickly, and in 2015had become brighter by more than five magnitudes in visible light. Since thistime V1318 Cyg S has remained at this maximum. Its spectrum shows littlevariability and consists of a mixture of emission and absorption lines, whichhas allowed for estimates of its spectral type as early Ae, with obviousevidence of matter outflow. We derive its current A(V)$\approx$ 7.2 and L = 750L(sun) thus confirming that V1318 Cyg S should belong to the Herbig Ae stars,making it, along with BD+40o4124 and V1686 Cyg, the third luminous young starin the group. It is very probable that we observe V1318 Cyg S near the pole andthat the inclination of its dense and slow ($\approx$ 100 km/s) outflow is low.The unusual variability and other features of V1318 Cyg S make it difficult toclassify this star among known types of eruptive young stars. It could be anextreme, higher-mass example of an EXor, or an object of intermediate classbetween EXors and FUors, like V1647 Ori.

New powerful outburst of the unusual young star V1318 Cyg S (LkH{\alpha} 225)