The Sister premiered on ITV on Monday night, and fans were particularly shocked when one viewer pointed out that the mysterious character Bob is played by Bertie Carvel, who portrayed Simon Foster in the hit show, Doctor Foster.
READ: Meet the cast of ITV's The Sister here
Taking to Twitter, they wrote: "Just realised Bob in #TheSister is the husband from Doctor Foster. He looks so different!" Viewers were equally shocked, with one writing: "Knew I recognised him but couldn’t place him," while another added: "Nooooo way! I fancied the pants off him in Dr Foster and didn’t even recognise him in this."
WATCH: Bertie plays Bob in the new series
A third person joked: "Thought there was SOMETHING I didn't like about him!" Viewers were also quick to discuss his character, with one writing: "I cannot take Bertie Carvel’s character Bob seriously. He’s like a mix of Fagin from Oliver Twist, Filch from Harry Potter, Pete Wicks from TOWIE & Captain Jack Sparrow."
Did you recognise Bertie?
Another tweeted: "Not sure if I love it or not? Quite confused, keep expecting the cast to burst into a rendition of 'You gotta pick a pocket or two boy' any minute now."
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Have you been enjoying the show so far? The synopsis for the new series reads: "Nathan has never been able to forget the worst night of his life: a party that led to the sudden, shocking death of a young woman. Only he and Bob, an eccentric old acquaintance, know what really happened… and they’ve resolved to keep it that way.
"But years later, Bob appears at Nathan’s door with terrifying news that threatens to tear Nathan’s world apart. Because Nathan has his own secrets now. Secrets that could destroy everything he has desperately fought to build for himself and his family."
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