Maclean was in Moscow until late 1939 , and so was present during the great Stalinist purges , observing the fates of Bukharin and other Russian revolutionaries . Although he was stationed in the capital , Maclean travelled extensively , primarily by train , into remote regions of the USSR which were off limits to foreigners , and was shadowed by the NKVD as he did so
great Stalinist purges
Great Purge
Sir Fitzroy Maclean, 1st Baronet