Hang on tight, folks, it's another ever so likely plot twist:
DanTom's late 'mother' was fathered by Jodie's late Dad.
(A bearing on DNA?)
Thus she was secret half-sister to Jason & Jodie.
(Perhaps making it fractionally easier for the abductors to justify their twisted actions to themselves?)
Rather hard wife's attentions (hopefully not including anything darker, which would be grim) were all focussed on Golden Child Jason and his high-flying school/career achievements. Resentment towards her, jealousy towards him, made him look elsewhere.
And neglect Jodie just as much as her mother did.
So fairly toxic set-up already.
Theories:
- Favoured daughter & architect husband: desperate for child yet unsuccessful (his fertility issues? Her cancer treatment? Limited time left?)
Dad and husband prepared to go to extreme and terrible lengths to solve that for her.
- Soon-to-be-Ex-best friend determined to steal Ben permanently/ start family together. Figures vulnerable Jodie will crumble after such a trauma, thus speeding up potential.
Jodie convenient scapegoat pawn for all.
Jodie's Dad, the secretly-shagging-your-husband 'friend', and half-sister/architect husband all collude on planning DanTom's abduction.
Jodie's late father pivotal to everything.
Does the title 'The Drowning' allude as much to his method of death (in bath) as DanTom's supposed one.
Was that really accidental? Or suicide after undergoing years of guilt, failure at achieving happy family, and repressed grief over favoured daughter's death?
Hmm...
But how does Jason fit in? ( "you owe it to Jodie..." ). Definitely covering up something major.