While it appeared her life was finally turing around following the shock news her ex-husband Simon was back in town - with his new wife and baby - her one night stand rang alarm bells for those watching on from home.
Gemma had a ball during last night’s instalment as she took her son’s teacher to bed, with Suranne Jones’s figure causing a social media meltdown in the process.
However, concerned fans for the doctor’s deteriorating well-being warned Gemma about James.
“Suspect there's more to James than meets the eye. Think he knew full well Gemma was Tom's mum. What's his game?” asked one alarmed viewer, as another agreed: “Thinking maybe this teacher, James could be Simons snoopy spy? Why else would be still be hanging around???"
Doctor Foster's James is hiding a big secret from Gemma?
A third cried: “Rlly hope James is perfect and not in on it….,” which was followed by: “James (the teacher) is one of Simons spies. How else would Simon have known that Gemma was in the club?"
Actor Bertie Carvel, who stars as scum bag Simon, suggested fans will come to forgive his villainous character.
“The first series was very much seen from Gemma’s perspective, but now Simon has his feet firmly planted more and has worked hard to show himself in a certain way, but that quickly breaks down and it leads to some really dark places,” Bertie told TV Times.
Gemma sleeps with James in Doctor Foster
Fans are concerned for their Doctor Foster
“The idea of what the comeuppance will be for Simon is absolutely a driver this time.
“I can’t believe he is irredeemable though and the theme of forgiveness is very powerful in the second series.”
More than six million people tuned in to watch the second instalment of Doctor Foster as the BBC drama beat Great British Bake Off in the ratings again.
Doctor Foster continues Wednesday at 9pm on BBC One.