The HBO drama The Undoing has been getting people talking, as Nicole Kidman and Hugh Grant portray a wealthy couple who get caught in the middle of a local woman's murder. Suddenly Grace Fraser sees that her husband Jonathan isn't the sweet and amazing doctor that she thought he was, and she must race to learn the truth.

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While some mysterious storylines get boringThe Undoing is a six-episode miniseries so the pace is fast and viewers learn something new in almost every scene. It's a perfect and interesting thriller with intelligent characters, although some seem smarter than others.

Henry Fraser

Henry from The Undoing on the phone

Jonathan and Grace's son Henry is adorable, and his biggest problem in the pilot is not being able to get a pet (and the mess he makes when making a smoothie for breakfast every morning before school).

While Henry could be precocious since he attends a fancy school, his rich upbringing and the bubble that he lives in make him fairly naive, so he's ranked low in terms of intelligence. He's terrified that his dad killed Elena, and that's something no child should have to deal with. Henry has been protected his entire life and that makes him seem younger than he is.

Miguel Alves

the undoing jonathan and miguel

Miguel is just a kid, and he's faced a lot of horrible things, from being sick to losing his mother.

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Miguel is ranked low in terms of intelligence because he's an innocent child, so it's definitely not his fault. He's sweet and sensitive, and instead of listening to his dad and going to school, he thought it would be a good idea to visit his mom at her art studio. Unfortunately, he saw her dead body, which is something that he can never forget.

Fernando Alves

The Undoing Fernando

Elena's husband Fernando doesn't make a lot of smart decisions, as he follows Grace around the city and talks to people he shouldn't be talking to.

Since he doesn't come from a world of privilege like the other characters, he doesn't have a fancy lawyer to give him advice, and he's living by his gut instincts. Unfortunately, those instincts steer him in the wrong direction.

Elena Alves

The Undoing Elena

Fans of the movie Gone Girl might like The Undoing, as Elena, the woman who is murdered at the start of the story, is a similar character. She's beautiful and mysterious, and she captivates everyone who meets her, while unnerving them at the same time.

Elena doesn't seem like a very smart person, as she got involved with Jonathan Fraser and it doesn't seem like she could tell that there's something off about him. She starts toying with Elena and she definitely gets in over her head.

Detective Joe Mendoza

The Undoing Detective Joe

A far cry from the sweet and quirky cops on Brooklyn Nine-Nine, Detective Joe Mendoza thinks that he's a lot smarter than Grace (and probably anyone else who he interviews).

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Mendoza is arrogant, but that doesn't necessarily translate to intelligence. He doesn't seem to know how to run a proper investigation as all he does is upset Grace instead of getting the answers that he wants. It's not a very straightforward process, and if he was smarter, it seems like would handle himself better.

Jonathan Fraser

the undoing jonathan

It was exciting when Hugh Grant joined The Undoing as Jonathan Fraser, and this character is somewhere in-between a super smart and a naive person.

On one hand, he's an accomplished doctor who has been at the top of his field, and he wouldn't have risen through the ranks without some intelligence. On the other hand, he was silly enough to have a public affair that got him fired and ruined his family life. He likes to be in control of every situation and while he can tell that he doesn't want to be like the other rich parents at his son's school, he does make a lot of wrong choices.

Sylvia Steinetz

the undoing sylvia

Nothing gets past Grace's friend Sylvia, who is a confident mother and lawyer. She moves through life with a sense of confidence and it appears that she has a closer connection to Jonathan than Grace originally thought, as Sylvia represented him in the case when he got fired.

Sylvia is highly intelligent and she also seems to live by the motto "keep your friends close and your enemies closer." As of episode four, it's unclear how involved she is and whether she's actually a good friend to Grace.

Franklin Reinhardt

the undoing franklin and grace

Donald Sutherland's The Undoing character, Franklin, is an incredibly perceptive person. He could tell that something was off about Jonathan from the start, and while it's a shame that Grace's father didn't support her marriage, it's interesting that Franklin knew the truth.

Since Franklin had his own affairs, he saw something similar in Jonathan and knew that he wasn't the right partner for his daughter. He enjoys his wealthy lifestyle and visits art galleries and museums frequently, and he's smart enough to know when to tell Grace a hard truth and when to offer her a safe place to land.

Grace Fraser

the undoing grace and henry

After starring in many popular movies, Nicole Kidman has been getting into prestige dramas on TV, and watching her play therapist Grace Fraser on The Undoing shows how talented she is.

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Grace is very conflicted, as she's still in love with her husband, but she can't believe that he would cheat on her and also be accused of murder. She's one of the smartest people on the series as she can tell when people are hiding something thanks to her training as a psychologist. There was no way that she could have known the truth about her husband's nature, and now that she is learning more about him, she's doing what she can to protect her heart and her son Henry.

Haley Fitzgerald

haley on the undoing

Haley Fitzgerald is so brilliant and good at her job that she makes The Good Wife lawyers look like they don't know what they're doing.

With her approach to her cases, which includes not cracking jokes and making sure that she knows everything that is going on, it seems like Haley can win anything. She has an interesting way of looking at her work: she says it's all about "muck." She explains, “People hire me to create muck" because she will "muck up the State's case." She can see through anyone who is lying to her and no one could ever mess with her. Fans can't wait to see what happens when Haley gets deeper into Jonathan's case.

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