Space Jam Confirmed
But, that's just it -- they don't even have to drop everything. Let's say they're running through Chap 1. They have the two starting quests and the quest for the town their in. That's 2nd level and a good bit towards 3rd. Unless they're running around Ten Towns collecting lots of town quests, when they hit third they'll probably only have one Chap 1 quest on the docket, possibly two, which aren't enough for reaching 4th level. At that point, they are not abandoning anything at all to go after the rumor -- it's teed up and next on the docket!
Regarding the two "starting quests" - and admittedly the designers could have made this considerably clearer - they are not meant to be completed first, only GIVEN first.
The main purpose of the starting quests is to prompt the adventurers to move from town to town, accruing and completing other Tier 1 quests. In fact, only when the DM decides that it's about time to move on from town-hopping and low-level questing should the starter quest (or quests - honestly there is no reason not to give them both although the book says one or the other) meet their resolution.
In other words, the people complaining that the serial killer is too tough for a level one party are correct, but they shouldn't be facing him at level one. In fact, the adventurers should not find him until they are close to the end of Chapter 1. So adventurers will likely reach level 3 or 4 en route to completing their starting quest(s).
So the idea is yes, we've heard there might be a crashed spaceship or whatever out there, but dammit Jim we've still got a serial killer on the loose right here in River City so those aliens are just gonna need to cool their jets for a bit.
The people complaining that the serial killer quest is lame because there is no investigation involved...have a point.