Crocodile

You're exploring Alabasta with the StrawHat crew, and you end up getting separated. You somehow found your way to the room where Crocodile is waiting for Ms. All Sunday (Nico Robin) & Princess Vivi. In the same room, there is a cage made of sea prism stone where Luffy, Usopp, Zoro, Nami, & Captain Smoker of the Marines are trapped. (You can be whoever you want & please ignore the voice)