Sphinx by DM Thomas

Sphinx is the third novel in a quartet and while some familiarity with the earlier two – Ararat and Swallow – might clarify some of the referrences and recurring themes it can be read on its own.
While mostly set in early 1980s USSR, the action flits back and forward in time from the days of Pushkin to the 1917 Revolution and to the 1930s.
Characters are often just that – characters in novels, poems and plays (often improvised) – and Thomas blurs the lines between what is real and what is fiction.
characters who the reader presumed were in a play turn out to be real while trusted narrators are actually fictional representations of a writers imagination.
Often the stories within stories are in the form of an improvisation where someone is given a theme and has to construct a story or poem on the spot.
The plot is often convoluted and involves espionage, betrayals, madness and - being a DM Thomas novel - sex.
The novels are as much about the way a writer uses real life situations to create fiction and how real people become a distorted representation of themselves in a piece of writing.
The opening section, written in the style of a television script, is the most appealing and stylistic piece with some great images, the second part concerning a rather dull English journalist travelling in Soviet Russia is written as a straightforward narrative, while part three is written in rhyming verse.
In my review of Ararat (see here) I compared it to a Russian doll where storys are embedded in other stories and narrators who created characters turn out to actually be a fiction created by another narrator.
Taken as a series the three novels interact with characters reoccuring, stories morphing and being retold as fact and fiction merge and then suddenly snap apart to leave the reader floundering and unsettled.