A treasure hunter and his comrades have drinks in a bar as Forever Season 1 Episode 18 begins. They've made a big discovery and he cautions his mates to keep their secret. Later that night, he is murdered on board his ship.
Henry and Abe discuss Henry's long life and many stories when Jo arrives to ferry Henry away to a crime scene. Henry and Lucas discover the captain was murdered by a harpoon to the chest but was also suffering from decompression sickness. Before his death, Rasmussen found gold. Traces of it were found on his body.
Jo, Henry, and Hanson visit the late captain's storage facility. While looking through his belongings, Henry finds items from the ship on which he first died.
When Henry returns home, Abe notices he's upset. Henry tells Abe the story of their family and that the ship was one of his father's. Henry was on the ship not just to provide medical care to the slaves and crew on board the ship but to free the slaves his father's company was transporting and ruin his father's empire. They learn that the ship was found 1,000 miles away from where Henry believed it sank and decide there must be more to the ship's story which Henry does not know.
Jo and Hanson crash Rick Rasmussen's wake but no one will talk to them. The salvage workers don't talk to cops. Henry observes the crowd and finds at least three people who were on Rick's.hip though none of them will admit to being there. Henry follows them outside and Jo and Hanson arrive and arrest them.
Davey, Margo, and Chappy are the prime suspects in Rick's murder. Henry asks to sit in on the interrogations so he can glean information about the ship from the suspects. When Henry learns that there was a map, he becomes adamant that the police find it. The lieutenant disagrees and tells him they'll call him when they need him. He and Abe decide to break into the warehouse to look for their own clues about the ship.
They find a chest of human remains, the skull of which Henry recognizes as belonging to the slave he promised to free. Before long they're joined by one of Rick's associates who trashes many of the artifacts while looking for Rick's gold. Henry chases him out of the storage unit and right into the cops.
Jo covers for Henry and leaves Abe out of her report. She wants him to leave the ship in the past so that they can solve the present-day murder. Jo and Hanson question the bar owner who toasted Rick at his wake and he points them in the direction of the wealthy financiers who often bankroll dives.
Henry and Lucas recover the coffin containing the remains from the Empress. They find it odd that there are any remains at all as most slaves who died on board were tossed into the ocean. Henry remembers the night he failed to give the key to the man before Jo enters his office. She has a lead on the man who bankrolled Rick's expedition and wants Henry to attend an event. Henry wants to change to be more appropriately dressed but Jo says no.
Jo and Henry meet the financier who blows them off in order to give his speech. He reveals the gold missing from Rick's find and then donates it all to a history program.
While Jo and Henry talk to Isaac Monroe, who tells them Rick willingly handed over his gold, Henry gets a call. He steps away to take it and Isaac flirts with Jo.
Henry answers the phone to find Adam on the other line. He's also at the event and believes the Empress of Africa holds the key to their curse. Adam has found the weapon used in Henry's first death. Adam slips out of the room while Jo enters.
The next day, Jo receives roses from Isaac. Hanson tells her he's clear for Rick's murder and encourages her to go on a date with the wealthy businessman. Lucas brings Henry a package. Adam has purchased the flintlock for Henry. While discussing the weapon with Lucas, Henry stumbles upon a genetic similarity between a deceased diver and one of the members of Rick's crew.
Jo arrives for her date with Isaac, clearly nervous and absent her husband's wedding ring. Henry tells Hanson and Reece about Margo and the dead diver. Margo gets into an elevator.
Isaac and Jo discuss her job and he tells her that for that night, she doesn't need to be a cop. She turns off her phone and puts it away. Margo is breaking into an apartment. Just as Isaac is about to kiss Jo, she excuses herself to the restroom. It was Isaac's apartment Margo was entering.
In the restroom, Jo talks herself out of being on the date with Isaac and hears a crashing sound outside. She leaves the room to find Isaac on the floor and Margo holding a knife. The women begin fighting while Henry and Hanson arrive and begin knocking on the door. The men can only hear the sounds of Marvin Gaye's "Let's Get It On" playing inside and wonder if they're interrupting unnecessarily. Jo had her gun after all.
At the precinct, Jo and Hanson fill Isaac in on Margo and Rick Rasmussen's death. Reece and the lieutenant leave the room and Jo tells Isaac it's okay if he doesn't want to go out again. He scoffs at her suggestion and tells her not to bring her gun next time.
Henry stops Isaac on his way out of the building and asks about the Empress. He knows the Empress was Isaac's obsession and not Rick's and Isaac tells Henry a story. On the night Henry died, he dropped a key as he was being carried above board to be tossed into the ocean. The slaves used the key to free themselves, took control of the ship, and sailed it to free land where they lived as free men. Isaac is one of their descendants.
Adam calls Henry that night and says he believes they only thing which can kill them is the weapon which killed them first. He wants Henry to test the theory.