The Undoing's episode five left viewers in shock last night as Nicole Kidman's character Grace made a shocking discovery. Warning, spoilers for episode five ahead!
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The episode, which aired in the US on Sunday night and has been available to watch on Sky and NOW TV in the UK since Monday morning, saw Grace tidying up her teenage son Henry's room, only to discover that the murder weapon, a sculpting hammer, was hidden in his violin case.
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In the final moment of the episode, she looks at him in shock only to find that he was awake, and watching her.
Fans were undeniably surprised by the plot twist, with one writing: "Me trying to figure out why Henry has the hammer when y'all convinced me last week that the blonde lady friend did it #TheUndoing #TheUndoingHBO."
Could Henry be the killer after all?
Another added: "Omg! I didn’t even consider Henry as a suspect. Dude... these cliffhangers!" A third person wrote: "Either Henry did it or he’s hiding that Jonathan really did it."
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The latest episode revealed that Henry knew more about Jonathan's affair with Elena than he originally let on, admitting to Grace that he saw them being intimate outside of his school.
Who do you think killed Elena?
It was also revealed that Jonathan's younger sister Katie was killed after being hit by a car when he was supposed to be looking after her, with his mother telling Grace that he never expressed any emotion over her death, hinting that he is a psychopath.
One viewer believed that the trait might have been passed down to his son, writing: "So many subtle scenes throughout this entire series have hinted at Henry having sociopathic tendencies. Not sure yet if he actually committed the murder or he's just covering up for his dad, but either way they def just tried to show that he's a sociopath like his dad."
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