A longtime reader writes:
I'm wondering if you -- or even your readers, if you think it'd be fitting to pose the below question to them -- could recommend a history of marxism that could serve as an alternative to Kolakowski's comprehensive yet superficial Main Currents. Is there another work out there that covers as much ground but is more philosophically in-depth?
I can't think of anything, but will open comments for suggestions. The best bet is probably to look at philosophically serious and informed treatments of particular thinkers/movements within the Marxist tradition.