Paradox Hotel - Rob Hart

"A locked-room murder mystery set at a hotel for time travelers--in which a detective must solve an impossible crime before her own grip on reality crumbles--from the author of The Warehouse On any ordinary day, the Fairbanks--affectionately known to its staff as the Paradox Hotel--is packed with ultra-rich tourists dressed for a dozen different time periods, all anxiously waiting to catch their "flights" to the past. And as if that weren't strange enough, proximity to the timeport makes for some odd side effects.

The clocks run backwards on occasion, and ghosts sometimes stroll the halls--or so it's whispered. Now, though, half a dozen of the world's most powerful people have arrived for a summit. Or maybe auction's a better word. The prize: no less than control of time-travel technology itself. On top of that, the hotel's snowed in, and the timeline's acting even stranger than usual. Which means nobody's leaving until further notice. And there's a killer on the loose. Or, at least, that's what head of security January Cole suspects. Except the corpse she's found is one that, somehow, only she can see. And the accidents starting to befall their prestigious guests...well, the only way those could be assassination attempts is if the killer's operating invisibly and in plain sight, all at once.

Which is surely impossible. And...well, even January's got to admit her credibility's not as strong as it could be. Because her gig here amounts to paid retirement, a pity posting for a former agent whose temporal perceptions have been so scrambled by the effects of timeline radiation that she's not fit for active duty. January's sure her condition is letting her glimpse something others can't. But she also knows her symptoms are getting worse--which means she might not solve this puzzle before she loses her grip on reality altogether"--