Twisted Sense

From Goodreads.com

On November 22, 1963, three shots rang out in Dallas, President Kennedy died, and the world changed forever. 
If you had the chance to change the course of history, would you?  Would the consequences be worth it? 

I'm a time travel junkie.  I love love love to read anything time travel, watch movies about time travel... I'll even spend a couple days' worth of time on archived Internet forums reading about a guy who claimed to be from the future searching for a piece of an old IBM computer (John Titor fans, hello!).  So when Stephen King's 11/22/63 was released, you can bet a time-travelling phone booth or two that I was gonna read it.

This book began with a delicious concept - a wormhole placed randomly in the back pantry of an old diner allowed for the traveler to be transported back in time to 1958.  Any changes effected upon the past would still be in place upon return to the present, but returning back to 1958 through that wormhole again will "reset" the changes entirely.   Go back in time, spend a couple of years wreaking havoc and having fun, come back to now, go back in, and any damage caused is undone - no hard feelings.  No consequences.

Al, the owner of the diner where our friendly wormhole keeps residence, has concocted a plan to go back in time, wait until 1963, and save Kennedy from assassination.  He'd do it himself, but lung cancer isn't patient, so he asks Jake, our main squeeze, to follow through.  Al's taken notes, gone back in time numerous times (resetting the past with each trip) and feels almost certain Oswald acted alone.  Jake's job is to take the "almost" out of that equation, and ultimately save Kennedy!

Along the way to 1963, Jake attempts to adjust the lives of some unfortunate people whom he knows in his current iteration.  While a school teacher in real life, he poses as a contemporary-to-the-late-1950s version, as well.  He falls in love.  He commits murder.  He saves lives.  Ultimately, his goal to save Kennedy has an unexpected ending.