I kind of hope they will use something like this for a season 3:
One of the ferries traveling from Calais to Dover explodes in a blazing inferno on the english channel, killing all 1000 passengers on board. Karl and Elise, who are now in a relationship, are being assigned to the case.
I think the whole ferry thing could make for a very interesting plot point.
Sounds good to me. Of course the ferry has to explode on the precise dividing line in the channel water that separates France and the UK. :-))
Any storyline is good for series 3, as long as there IS a series 3.
Well, the exception to "any storyline" would be the one they had to resort to in the original version Bron/Broen, when they basically wrote out the Martin (Karl) character of the series, and we lost Kim Bodnia.
So I hope Stephen Dillane wants to do series 3, and they don't follow in the footsteps of the original Bron/Broen.
The series of Bron/Broen without Kim was good. But when you break up the seminal team in shows like this, a lot is lost that can't be replaced.