The moral of Matt Ruff’s Set This House in Order might be: watch out for the eggnog – especially if you can’t be entirely sure who’s drinking it.Baffled? You should be. The hero of this complex novel of suspense from 2003 is a so-called “multiple,” an individual whose personality splits into separate identities or “souls” in response to a massive childhood trauma. The lead personality is called Andy Gage – but as we soon learn, he’s got some heavy competition.The book opens with an account of Andy’s birth and his complicated mental landscape.With the help of a good doctor named Danielle Grey, my father worked to establish order. In place of the dark room, he constructed a geography in Andy Gage’s head, a sun-lit countryside where the souls could see and talk to one another. He created the house, so they’d have a place to live…The effort to construct the house exhausted my father, and left him with little enthusiasm for dealing with the outside world. But someone had to run the body; and so, on the day the last shingle was nailed in place, my father went down to the lake and called my name.It’s a strategy that works. Despite the rival personalities in his head – which include a foul-mouthed adolescent, a Greek fitness fanatic and a banished evil spirit called Gideon – Andy Gage becomes a functional member of society, holding a job at a Seattle software company.But in order to maintain control, the Andy Gage personality has to keep a clear head. And that becomes a problem when his boss offers him a whiskey-laced tipple at the company Christmas party.…Julie came back, carrying a mug in each hand. “Cheers,” she said, handing me one.“Cheers.” I took an experimental sip…and frowned, tasting liquor in with the eggs and cream. “Uh, Julie…I think you forgot, I don’t .” “Shh,” Julie said, pressing a finger to my lips. “I won’t tell if you won’t.” It wasn’t a question of telling or not telling, of course; hiding a drink from my father would be like hiding a manicure from my fingernails.Matt Ruff has enormous fun with this bizarre scenario. As the plot unfolds and Andy is forced to confront the trauma in his past, he becomes something of a superhuman detective, who always has his foes outnumbered.If only it weren’t for his own personal Kryptonite – whiskey. After inadvertently killing a fugitive murderer and learning that the doctor who helped him cope with his condition has died, the strain gets to be too much and Andy fatefully hits a bottle of hooch.I fell into the lake; but somebody has to run the body.And somebody did: ran it, and ran with it: somebody who had been waiting a long time for just this chance. Even as the waters closed over me, Andy Gage’s body was on the move again, running back into the street, back into the night; running far, far away.The body’s flight leads our hero back to his home town and the past horror he was created to overcome.Set This House in Order won praise for its realistic treatment of “dissociative identity disorder” – a controversial condition that not all psychiatrists accept or agree on how to treat. Ruff said he was fascinated by the narrative possibilities of turning one character into various characters taking turns in the body of a protagonist.I was fascinated as well. I began reading this unusual work of fiction one lazy Sunday morning and didn’t put it down until it was dark outside, and I’d gone through the entire labyrinth within Andy Gage’s head. Matt Ruff’s House is an utterly intriguing place to be.