Grandpa Jack is an non-player character located in a house in Hemenster, and also south of East Ardougne Zoo near the Clock Tower.
He is involved in the Fishing Contest quest, which he reveals that he took first place in four years in a row, although he is far too old to compete now. He gives the player a hint about how to win, which is to go to McGrubor's Wood and dig up Red vine worms from the vines. This requires a spade and players should be careful as Guard dogs patrol the area.
- If a female player talks to him, he will address the player as young man. This is an oversight, as some quests were programmed to properly address the player by their assigned gender.