Marisabel's Adventures
Marisabel Discovers the Whispering Chest
Marisabel discovered the wreck of the Silver Blade near the island where she grew up. While exploring the wreck, she found the Whispering Chest with a notice in Merfolk language that reads "Do Not Open". Unsure of what to do with it and as she previously found earrings that allowed her to talk with Merfolk, she went to a meeting place on an island near Golden Sands Outpost to return this mysterious chest to the mer people.
However, the Merfolk reacted viscerally to the presence of the Chest, warning not to open it or throw it in the sea. The mer fled as soon as the Chest began to hum.
Source
Tales From The Sea of Thieves
Marisabel meets with the Twisted Knife
Marisabel decided to sell the Whispering Chest to any merchant or vendor willing. As she was trying to find someone, her ship is assailed by The Salty Hippo and another ship. They fought them off and took Cole, the captain of The Salty Hippo, captive.
Cole revealed himself as a member of a group of bounty hunters known as The Twisted Knife. Whilst in the brig, he elicited knowledge about Flameheart Junior and the Whispering Chest, revealing that they were hired by a patron who had sent many before to retrieve the Chest.
Source
Tales From The Sea of Thieves
Mutiny of the Plundered Crown
Cole betrays Marisabel by drugging her food, locking her up, killing Nine-Cat Nura, and turning her crew against her whilst she is out. Marisabel swore vengeance before she was sent to the Ferry of the Damned.
Marisabel and Nine-Cat Nura reunite and track down The Plundered Crown, taking it back the ship from Cole and The Twisted Knife with the help of Jean.
Source
Tales From The Sea of Thieves