Spoiler warning: this article concerns the second series of Doctor Foster, so don’t read on unless you’re up to date with the BBC show
The first season of Doctor Foster was utterly all-consuming, tracking the gradual erosion of a marriage in toe-curling – and irresistible – detail. Now, back for a second run, Mike Bartlett’s tale of feuding ex-spouses feels more deranged, more addictive, more…
Well, more of everything. Including carefully veiled (but still earth-shattering) plot twists, if diehard fans are to be believed.
Episode one concluded with Simon (Bertie Carvel) slithering back into Partminster with pregnant fiancé Kate (Jodie Corner), setting up in a glass mansion, stealing all of his ex-wife’s fickle friends and persuading their teenage son, Tom (Tom Taylor) to walk out on his mother.
Naturally, our titular doctor, Gemma Foster (Suranne Jones) was left absolutely furious by this turn of events – and, in the second episode, it quickly becomes apparent that her life is rapidly spinning out of control (see her disturbing encounter with teenager Max, if you don’t believe us).
It makes sense, then, that she has decided she needs to forge a few more alliances. And, when she spots Tom having an appointment with her prickly new colleague Sian (Sian Brooke), Gemma makes it her mission to get to know her co-worker better.
Keen to break down the pesky barriers of doctor-patient confidentiality, Gemma orchestrates an intimate dinner party and refills Sian’s glass far more frequently than necessary. It’s not long before Sian is drunk and lets slip that she’s treating Tom for anxiety and sleeplessness (understandable, considering the tensions between his warring parents).
But then Sian starts talking about her own family – particularly her son, Harry.
“Harry is the product of an unhappy and short-lived relationship with a man called Evan,” she tells Gemma. “Evan had issues, which when we were young were charm and ambition, but as he got older were revealed to be hidden as an aggression.”
Sian added that her abusive ex is a “s**t” and that son Harry never sees him.
But is there more to her tale than meets the eye?
Taking to Twitter, viewers have been quick to speculate that there is no Evan – and that Harry’s dad is, in fact, Simon himself.
Too outlandish a theory? Possibly – but there’s no denying that he has form when it comes to infidelity, and he definitely has a dark, manipulative side. Need proof? See him stealing away Gemma’s son, cutting her off from her friends, delivering that flower tribute, and booking in estate agents to value her house, when it most definitely is not for sale.
More compelling, though? That photo of Sian's son looks remarkably similar to Tom.
#doctorfoster Sian's sons father is Simon and I reckon Gemma will get absolute hell from Max's parents and Tom will tell all to his mum— REBABIBA (@RebaBiba) September 13, 2017
Woke up wondering if Simon is the father of Sian's son #DoctorFoster— Kate Jones (@Kipakate) September 13, 2017
I think Simon is Sian's Son's Dad - this is too tense! #DoctorFoster— Esmé Roberts (@Esme_Louisex) September 12, 2017
And some have speculated that the circumstances surrounding the two boys’ births could be very similar, too.
Website Den of Geek, leaping upon the fact that Tom is so upset with his mum, has taken a closer look at “the facts” Simon told his son in order to provoke such an emotional reaction.
“It could have something to do with timing,” they point out. “Tom’s age as a 15-year-old was mentioned twice this week, as was the duration of Gemma and Simon’s 15-year marriage and the fact that she hadn’t had a night out like that one in 15 years.
“Marriage and parenthood seem to have happened in very close succession for Gemma and Simon. Did she get pregnant by accident? And did she, initially at least, not want to keep the baby?”
Cruel potential facts for a father to hurl into the face of his son – but it also suggests that, like Harry, Tom was “the product of an unhappy and short-lived relationship”. Only, unlike Sian, Gemma was persuaded into marrying the coercive father of her unborn child.
Before we get too carried away, it’s worth noting that Sian went to Warwick University with Simon – and that they’re apparently on friendly enough terms for her to ask him about the job which opened up at the practice (Simon told her that his ex-wife worked there, but would likely be gone “in a month”).
Since then, she’s seemingly been feeding him information about his ex all this time. Sure, she claims her actions are completely innocent… but are they?
Is Sian succumbing to Simon’s demands in a bid to protect her (their?) son from him. While she’s seemingly bonded with Gemma over their malevolent exes (who may or may not be the same person), we don't doubt that Sian would still feed Simon information about her new BFF in order to keep him away from Harry?
Or perhaps there’s even more to their relationship than viewers suspect.
Speaking about her character, Brooke said simply: “There’s definitely more to her and that is what drew me to the role. It’s the skill of Mike Bartlett’s writing that each character is never what they seem.”
Remaining coy about any specific details, she added: “Sian knows more about Gemma’s personal life than you might expect. She is somebody who prides herself on her work and is a high achiever. She is also fun to play because she will say things to people – totally unaware she is treading on their toes.
“She is lacking that filter in her head, which is a great pairing with Gemma who is also confident and forthright. Therefore the rivalry between them develops.”
We guess we’ll have to wait until the next episode to find out more…
Doctor Foster continues next Tuesday at 9pm on BBC One.