Last night's Lost was another thrilling hour of flashbacks and flash-forwards, culminating in a shocking event - even by the standards of a show that makes its living around them.
If someone from the future goes back 30 years and shoots a young version of someone they know in the present time, doesn't that throw off the whole space-time continuum?
We have no idea, obviously, since when you're writing about time travel, all bets are pretty much off to begin with. But it may take an encyclopedia of Lost spoilers to explain.
For a full rundown of last night's events in 1970s DHARMA-land and in the life of Sayid Jurrah before he got there, follow the link for our detailed recap of "He's Our You" ...