Frank was present at the Battle of the Archipelago, during which the pirates of Mos Le'Harmless, under Gentleman Mallard, attempted to defeat the infamous Rabid Jack. Redbeard played a relatively minor role in the battle, although he did prove a great asset to his captain, Hector.
Following Hector's eventual death, Frank became the ship's new captain. He is currently docked in Port Sarim, although his ship and crew are nowhere to be seen.
During Pirate's Treasure, players must smuggle Karamjan rum onto the mainland for Frank, who has offered them access to Hector's old treasure. Players must smuggle the illegal drink in on a banana shipment from Luthas's plantation in Musa Point, Karamja.
Once players get him the rum from Wydin's local grocery store, they must bring it to Frank, who will then give them the key to Hector's chest in the Blue Moon Inn in Varrock. This, in turn, will point them to Falador Park, where the treasure is buried and the quest is completed.
When players bring the letter to Frank, he will remain unconvinced, and ask that they instead get a signature from Captain Donnie, the captain of Jack's ship The Inebriated. Eventually, the player manages to get the signature from the pirate 50% Luke, convincing Frank to give them his mark.