He became a member of the Communist Party (KPD) in 1931 and moved to Moscow, where he initially participated in Marx-Engels-Gesamtausgabe, the ambitious project of a complete edition of the works of Marx and Engels.
[2] He also published an article on Marx and the Democratic Association of 1847 in one of the first editions of "Science and Society", the leading Marxist publication in the USA.
[3] Haenisch's connections to Western countries and culture as well as the earlier accusations which led to his dismissal from Marx-Engels-Institute raised the suspicion of the NKVD, which arrested him in March, 1938.
In June, 1938, Haenisch was sentenced to death for "espionage" (like thousands of German communists) and subsequently shot at Butovo firing range and interred in a mass grave there.
She later married German geologist Friedrich Stammberger, worked as a lecturer for Dietz Verlag Berlin, was a lifelong member of SED (and successors PDS and Linkspartei) and died in 2005.