Inconceivable is the story of two women who've been best friends since high school, now at the centre of a group of female friends, all in their mid-thirties and facing the first few years of getting pregnant and child-rearing while each holding down their demanding jobs. In the midst of this friend group is a lingering affair, a struggle with infertility, fierce competitiveness, even fiercer love and something unthinkable.

Four friends head off for a boozy weekend that spirals out of control when the lover of one of them turns up unexpectedly for the party.