A major literary figure who's largely unknown: Victor Serge

Seems that, for no clear reason, I've been various incarnations of spy fiction, some more successful than others, and the latest I've started is Victor Serge's Unforgiving Years, from the great NYRB, edited and translated (from French) by Richard Greeman. Serge wrote this work, his final (and 7th) novel in 1946-47, the year he died; he knew this (and his other 2 final novels) would never be published in his lifetime, and he was right - it was first published in 1971. I broke w/ my usual convention, which is to read the "introduction" after reading the novel, as most intros either give away too much of the plot or are hardly comprehensible unless you've read the novel and have some sense of the characters and setting. This novel is an exception: Greeman's intro is really smart and helpful and provides great background and context, especially in that, as RG notes, the plot of the novel is difficult to follow. Serge spent all of his life as a political activist and committed Marxist; he sided with the Trotsky faction and was as a result imprisoned several times by the Stalinist forces, finally gaining freedom and fleeing to Mexico, where he died in complete poverty and obscurity. Over the years, his 7 novels and other writings have been recovered and published and discovered and he is now recognized as a major literary figure - though one not familiar to most readers (me included). The novel itself is in 4 sections or "movements," first set in Paris in (as RG's note clarifies) about 1940 at or just before the start of the war. We follow a secret agent - known as D, or sometimes as Sascha - presumably a Soviet agent in Paris, who is trying to "resign" from his post while knowing that doing so makes him an immediate target. So over the first 70 pp or so we see him execute various stratagems to elude his pursuers while also linking w/ his fellow spy and love interest, Nadine (?), as they plan to escape from France. The writing is terrific and evocative - probably a foundational work for the great contemporary writer of Paris noir, Patrick Modiano, and the various subterfuges that D takes to avoid capture and death seem credible and authentic. Apparently, as RG's intro makes clear, each of the 4 sections is in a different locale, and I think the same characters are part of each section, though the structure is somewhat loose and at times elusive. Still, based on first impressions and first section of the novel, it's well worth staying w/ this sometimes challenging work.