The character Major Alexander Degtyarev from the video game S.T.A.L.K.E.R . is an experienced stalker and an SBU agent .
The player , a former experienced stalker and USS agent , Major Alexander Degtyarev , is sent into the Zone to investigate the crash sites on behalf of the army .
S.T.A.L.K.E.R.-COLON- Call of Pripyat