the problem with it being about a murder
Now, don't get me wrong, I'm very excited for this and have moderate hopes. But there is a problem inherent with having Season 1 of this kind of show center around a murder mystery:
What will happen in Season 2?
Which, granted, is always a challenging (and admittedly presumptuous) question, but having Season 1 be about a murder just makes it worse.
Here's why.
They'll essentially have two options in regards to the murder mystery of Season 1.
1: Reveal who the killer is by the end of the season.
2: Don't reveal, stretch it out.
The problem with Option 1 is that this leaves essentially two options for Season 2:
A: Season 2 is centered around another murder mystery.
B: It isn't.
The problem with A is that it would then feel like "What is this, a detective show? How many people can get themselves killed in this little town?"
The problem with B is that after a murder mystery, it would likely feel slow-paced, dull, boring by comparison.
And the problem with the above Option 2, if they don't reveal the killer, that'll just tick people off. The Killing tried that, and it drove people away. Scream and Scream Queens have also left threads hanging for the following season. Maybe that's the way Riverdale will go. Leave threads hanging, making the characters think they caught the killer, but the audience knows it isn't really over.
Like I said, looking forward to it, but concerned about the end of the season and a potential second season.