The sixth episode ends with the Liars reconciling in the past timeline (summer 16), and Gat choosing to forgo his scholarship opportunity in order to return to Beechwood. However, he’s stopped by the police before he could set foot on the island. They inform him that there’s been an accident. Here's what happens next in episode 7 of We Were Liars, titled "Everybody Knows That The Captain Lied."
Spoilers are ahead from We Were Liars episode 7.

Summer 16 (past)
Penny, Carrie, and Bess argue during the end-of-summer dinner
Summer is coming to a close, and the staff at Clairmont is getting ready for the big end-of-season dinner. Penny, Carrie, and Bess are all eager to stay in Harris’s good graces, hoping to secure a place in his will. Each woman instructs their children to be on their best behavior for the evening, but things do not go as planned. Gat is not in attendance at the dinner because he's believed to be on his way to New York for his interview.
During the dinner, Bess starts throwing her sisters under the bus. She shares with everyone that she knows about the video of Johnny beating another kid. She also announces to everyone at the table that she's aware Penny hired a lawyer to conceal some of her dirty secrets in her divorce battle. Carrie then retaliates by telling Bess that she should cover up the scratch marks on her back from salty Dan. Earlier in the episode, Bess hooked up with salty Dan again. Cadence, Johnny, and Mirren look at their parents in shock.
Fed up with them, the Liars begin embarrassing their parents in front of Harris. As Cadence continues to bring up Gat, Harris becomes enraged. She then questions him on why he never actually calls Gat or Ed by their names. Johnny joins in, and Carrie tries to quiet him. But Johnny is even more furious now, having just learned at the dinner table that she only broke up with Ed because Harris gave her an ultimatum.
Things really get out of control, and Harris stands up from his seat, announcing that he's going to have his lawyer obtain the papers for his will and have them filed in the morning. He tells his daughters that inheritance will no longer play a factor in who gets what of his and that it'll be based on what he thinks they have earned. He leaves the table afterwards.
Harris has a bad fall
Still unwilling to let the conversation go, Cadence follows Harris outside and confronts him about his disdain for Ed and Gat. She accuses him of being racist, pointing out that he only pretended to accept them to maintain his reputation. But when Carrie and Ed began discussing the possibility of having children, Harris's real feelings came to light.
He didn’t want mixed-race grandchildren, and when Carrie approached him for help, he seized the moment as the perfect chance to drive Ed away for good. Just as Harris places his glass down and turns around to face Cadence, he accidentally trips on the patio steps and hits his head on a piece of hard rock. Blood immediately starts pooling around his head. Cadence yells for help.
The Liars decide to set Clairmont on fire
A helicopter arrives at Beechwood and airlifts Harris to the hospital. It turns out the final scene in episode 6 wasn’t about Cadence’s accident, but about Harris’s sudden medical emergency. Before Penny leaves with Harris in the helicopter, she tells Cadence to find his will and burn it if it doesn't favor them.
As Bess packs some of Harris's things into a bag so she can take it to the hospital, she has a meltdown in front of Mirren. Elsewhere in Clairmont, Carrie tries to look for pills. Johnny approaches her and places a bottle of pills on the counter. He tells her that he's aware that she's slipping back into her old ways. Carrie stays mostly silent, simply gathering her bags and the pills before telling Johnny they’ll talk about everything tomorrow.
With the parents at the hospital and all the staff gone, the Liars sit outside talking when Gat suddenly comes running up to them. He managed to find a way on the island. Cadence runs up and kisses him, while Johnny and Mirren hug him. The Liars start cleaning up Clairmont. Cadence takes a break to find Harris's will. She and Gat have alone time later, and Gat tells Cadence that the reason he came back to Beechwood is because of her.
Penny calls the house and informs the Liars that Harris is okay, but his CT scans came back with some abnormalities. She ends the phone call after Carrie and Bess tell her that Harris is no longer in his hospital room. As the Liars sit around Clairmont, talking about Harris and his racist ways, Cadence runs and grabs his will. Then, they all meet outside by the fire to discuss the will.
According to the document, Harris planned to leave his Boston property to Bess and provide quarterly stipends to Carrie and Penny, but only if they remained unmarried. Cadence tosses the will into the fire, then makes a wild suggestion. She suggests that they should burn Clairmont down. As she says this, the will burns in the flames. But what’s truly shocking is what she missed in the will. Cadence didn’t notice that Harris had intended to leave Beechwood Island to her.
Summer 17 (present)
Harris takes Cadence into town
As Cadence chats with Mirren on the beach, Harris approaches and tells her that he's going to take her into town. Once they arrive, Harris buys Cadence candy before taking her to the town doctor. Cadence initially thinks he took her to the doctor so that she could be seen, but it turns out the doctor's visit is for him. Harris walks outside once the visit is over, and Cadence spots medicine in his hand. She asks him what the doctor said, and Harris gives her a vague response. It appears Harris isn't doing well.
Cadence learns the truth about what happened to Clairmont
At the very end of the seventh episode, Cadence's memories come back to her from the night of the end-of-summer dinner in summer 16, and she realizes that she and the rest of the Liars burned down old Clairmont. That's why the new Clairmont looks so different. It had nothing to do with Harris wanting to renovate. As Johnny and Mirren walk up to her, Cadence tells them she finally remembers what happened that night. They immediately take her hand, and the episode comes to a close.
We Were Liars is now available to stream on Prime Video.
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