Could he be onto something?
Isaac is intrigued when his brother Paul is mentioned and asks Kim about him. She's hesitant at first before admitting that he was murdered.
And after launching questions at the nurse visiting for Patrick’s trial, Isaac is irate when his dad formally agrees to take part.
As Patrick mulls over Isaac's mood, Kim admits she told him about Paul. Overhearing, Sheree check in with her son to make sure he's taking his meds after acting out. Knowing what it feels like to be lied to, Isaac now wants to be truthful but Sheree refuses.
Later, Patrick apologises to Isaac, explaining his regrets about the dishonesty between him and Paul. As the guilt eats away at Isaac, he finally comes clean to his dad who is left reeling at the revelation.
Sheree meanwhile, tries to blame Patrick’s stroke and covid for not being truthful sooner, but Patrick insists Isaac has nothing to be ashamed of. Sheree pretends to agree.
As he looks through photos of Paul, Isaac is struck by their likeness and muses to Lola about his brother being misunderstood. What if his schizophrenia diagnosis was a misunderstanding too?
When he spots Ash, using Patrick's trial as a cover, Isaac asks her about doctors getting things wrong, especially for ethnic minorities. Isaac's mind is left whirring as she explains some conditions are more likely to be wrongly diagnosed than others.
EastEnders continues Mondays, Tuesdays, Thursdays and Fridays on BBC One