Dan Brown’s Robert Langdon books aren’t complicated. All five of them adhere to the same formula, wherein Langdon, a middle-aged Harvard professor of “symbology,” gets wrapped up in an age-old conspiracy involving a secret society and must follow historical clues hidden in famous landmarks or artworks to solve a mystery with his attractive lady sidekick before a zealot of some form or another murders him. That’s it. Those are all the books. The international locations and cheesy thrills of the series lend themselves easily to adaptation, and three of the five (The Da Vinci Code, Angels & Demons, and Inferno) have appeared on the big screen in zippy, fast-moving films starring Tom Hanks as Robert Langdon.

The Lost Symbol on Peacock is the first time anyone has tried to stretch one of Brown’s books into a television series. This will be regarded in the future as a bad move. Not only is The Lost Symbol the novel the weakest of Brown’s five Langdon adventures (which is probably why no one made it into a movie), The Lost Symbol the TV show makes a critical mistake that renders the show difficult to watch: It makes Robert Langdon a total asshole.

In The Lost Symbol, Robert Langdon’s (Ashley Zukerman) wealthy mentor Peter Solomon (Eddie Izzard), a high-ranking Freemason, is kidnapped. Naturally, this becomes Robert’s problem, so he teams up with Solomon’s daughter Katherine (Valorie Curry) to follow an ancient path of enlightenment hidden in the Mason-inspired art and architecture of Washington DC. This is all par for the course for a Langdon adventure, except that this time Langdon is around 30 years old, which makes his Harvard-tested competence come off as arrogance and his nerdy need to explain things comes off as mansplaining nonsense.

Other portrayals of Robert Langdon have worked because he’s an unlikely hero. He’s older, a little awkward, and when played by Tom Hanks, he has a wry sense of humor about what a huge dork he is. The Langdon of The Lost Symbol is a dork who labors under the youthful delusion that he is either not a dork or the king dork to whom all other dorks must bow.

There’s nothing Ashley Zukerman could have done to make Robert Landgon less of a butthead.

In just the first episode, Langdon answers a call from the kidnapper and gets unreasonably pissy because the guy on the other end of the line explains what the “araf” is (it’s a state between life and death). Langdon also refuses to initially explain key details of the case to a competent CIA agent (Sumalee Montano) because “she wouldn’t understand.” That’s before the flashbacks to the time when he spent a horrible dinner mocking Katherine Solomon’s field of study (don’t worry, she still wanted to sleep with him), and the present day scenes where he continues to dismiss her expertise until she goes above and beyond to prove that she’s useful.

There’s nothing Ashley Zukerman could have done to make Robert Landgon less of a butthead; his insufferability is a problem with the writing of the show. The Lost Symbol has eight whole episodes to cover a clone stamp of the plots that took an hour–45 to get through in theaters, and trying to fill the dead space between the book’s sparse plot points is a challenge the show can’t overcome. Some expanded characters, including charming Capital security guard Nunez (Rick Gonzalez), Sumalee Montano’s empathetic update to CIA agent Inoue Sato, and Eddie Izzard’s frankly unhinged take on what an established American patriarch acts like add a little fun back into the show, but not much.

The Lost Symbol is a television show starring the guy you started talking to at a bar who’s spent 15 straight minutes explaining the Latin roots of common SAT words, and you’re starting to wish you’d just stayed home. Maybe as more episodes release, Robert Langdon will chill out and learn the life lessons that make him a solidly OK guy in his forties, but voluntarily sticking around until someone starts being nice has always been a sucker’s game. Both the audience and Katherine Solomon can do better.

The Lost Symbol is streaming on Peacock.