The Heart-Wrenching, Tragic Story of What Happened to Boo in 'Fleabag'
Fleabag struggles with the truth about Boo's death throughout Season 1.
Published April 28 2026, 3:54 p.m. ET

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Warning: This article contains major spoilers for Fleabag Season 1. It also discusses self-harm and suicide.
On the surface, Fleabag is an irreverent drama-comedy about an early-30s woman navigating life, dating, and feeling misunderstood. However, there's an undercurrent of grief, guilt, and deep emotional turmoil in the series.
One of the most devastating emotional storylines is about Fleabag processing the loss of her best friend, Boo. In the first season, Fleabag shares snippets about Boo's personality and eventually reveals the truth about her passing.

What happened to Boo in 'Fleabag'?
Fleabag calls Boo's death an "accidental suicide." Throughout the first season, the audience learns the story behind boo's death. After Boo learned that her boyfriend had cheated on her, she was extremely upset.
She decided to injure herself just enough to warrant a trip to the hospital so that her boyfriend would feel guilty.
Boo stepped out into a bike lane on a busy street, expecting to get hit by a bike. Unfortunately, the crash that ensued resulted in the deaths of three people, including Boo.

Fleabag's grief over the loss of Boo is complicated because Fleabag had a hand in the events that motivated Boo's unsafe behavior. The audience eventually learns that "the other woman" whom Boo's boyfriend hooked up with is none other than Fleabag.
Fleabag's grief is also complex because Boo helped Fleabag through the loss of her mother. In one scene, Fleabag says she doesn't know what to do with all the love she has for her mom now that she's gone. Boo says, "I'll take it. I'm serious. It sounds lovely ... You have to give it to me. It's gotta go somewhere."
Did Boo know her boyfriend cheated with Fleabag?
In a flashback, Boo says that she plans to get tangled up in a bike to make her boyfriend feel guilty when he sees her in the hospital. It seems that Boo never learned that her boyfriend cheated on her with Fleabag, which would have been an even bigger gut-punch.
In a later scene, however, Fleabag's sister, Claire, says that she can't believe Fleabag, "after what [she] did to Boo," so it's clear that at least Claire knows about Fleabag cheating with Boo's boyfriend.
A flashback early-on in 'Fleabag' gives the audience insight into Boo's character.
In the flashback, Fleabag and Boo are working at the cafe when Fleabag shares a headline about an 11-year-old boy being sent to Juvenile Prison for mistreating a hamster.
Instead of labeling the boy as violent, Boo shows empathy for him and questions why authorities simply sent him to prison instead of getting him help.
"They shouldn't have just locked him up ... He's obviously not happy. Happy people wouldn't do things like that," Boo says.
Boo says, "That's the very reason they put rubbers on the end of pencils ... Because people make mistakes." Boo was so kind and understanding that she may have even forgiven Fleabag had she lived long enough to learn the truth about what really happened.