Talk:Murder at the KOGETSUKAN/@comment-4802891-20180514193732/@comment-4802891-20180515071417

He knows the families are from America, but we don't know where they are. However, Full moons occur at around the same time all over the world, with only a day or two off (or rather, hours, as it overlaps). If Sherlock checks outside Chaldea and the moon is let's say in its first quarter, he would know that the action indeed takes place a few days in the future, and MC should be "safe".

It's possible that our actions here will save the day and no one will die thanks to it.

However, if Sherlock discovers the moon has already passed the full phase, it means we are too late regardless and are witnessing past events.