  Aiming to explore weak spectral features of stellar and interstellar origin
we used the NES echelle spectrograph of the 6-m telescope to obtain
high-resolution spectra for 13 hot O3 - B4 stars in the Cyg OB2 association,
including a high luminous star No. 12. Velocity fields in the atmospheres and
interstellar medium, characteristics of optical spectra and line profiles are
investigated. The cascade star formation scheme for the association is
confirmed. Evidence is presented suggesting that the hypergiant Cyg OB2 No.12
is an LBV object and that its anomalous reddening has a circumstellar nature.
