I have now watched all 6 episodes, weathered the numerous rows, love-making scenes and baby delivery scene (why do they always make female actors do this, it's like asking a pianist to play Rachmaninov's Third) and shouted at the TV a few times. I am glad I did.
Karine Vanasse is remarkable, her character Evelyn is rarely happy for long, she is inconsistent, dis-satisfied with what she has and triggered at the smallest things, histrionic, dismissive, doesn't take responsibility for herself or accountability for her part of the problems they face, she deflects, moves the goal-posts all the time. She is encouraged in all this by her rather typical single female side-kick, who is hostile to Evelyn being in a couple and makes her disdain for the husband quite plain. Evelyn meanwhile - in various timelines - is not short of men, if there was ever a woman for whom the saying "she's not your girl, it's just your turn" was coined, Evelyn is that woman. Less Plan B, more Cluster B.
Vanasse plays this really awful woman with such sincerity and authenticity, her striking beauty and her range of expression is captivating, for example the grieving phone-call (spoiler) and the aftermath of this traumatic event (Episode 5, spoiler), her gentleness and loving nature when she and Phillip were happy, these moments were the calm before the confusing rug-pulling and door slamming storm usually.
There are various sub-plots and intrigues, which work well. Through it all, Patrick Adams' character Phillip really does try to do the right thing for other people, he means well, but he is caught in co-dependency with his brother and his awful mother, as well as with his wife, Evelyn, and nothing seems to work out. Until, he realises the one thing he has to do, to give all of them a chance to break the cycle and have different lives.
In a sense, Plan B is all about consequences, it uses a time-machine storyline to show how things could be different if people had behaved differently, if we had acted differently. It is potentially transformative in that, if only the characters in Plan B had made better choices, been more ethical, more direct, taken responsibility for themselves, they would not need to go back and fix things. This is the hidden payload in Plan B, live life in such a way that you do not regret your actions. This, for me, makes it more than a TV show.
Ironically, Plan B is also a morning-after pharmaceutical product, you'll get the irony when you see the show.