Dr Jekyll is still in game, but Hyde was discontinued from RuneScape after an update.
Jekyll and Hyde was a random event before the 25 February2009update that reworked random events. Occasionally, the player would be approached by a man named Dr Jekyll who desperately begged for help. Dr Jekyll approached the player and asked for the highest level clean herb that the player had; he asked for Guam Leaf if player had no herbs. In return, Dr Jekyll would give the player a potion (see list). A player could choose not to help, then Dr Jekyll would go find someone else to help him and the player received a strength potion(2).
If the player ignored him, he would transform into Mr Hyde (level 14-159, depending on the player's combat level), who fought with melee. When killed, he would drop a potion, similar to if he was given a herb. However, sometimes he dropped an empty vial. Killing him could sometimes be more profitable than giving him a herb, as he could possibly drop a Super restore potion (4).
Since the update that retired the random event, Dr Jekyll will occasionally appear in Varrock square and run to the Apothecary.
File:HydeTentacleEffect.jpgStarting with the release of HD, Hyde had this "tentacle effect" graphic glitch, which was fixed on 29 July 2008.
The list, which potion Dr Jekyll gave for the herb:
*For Ranarr and above, the potion given is 1 level below the herb
Dr. Jekyll visits the Apothecary in Varrock
Trivia
The event is a direct reference to the mystery novel Strange Case of Dr Jekyll and Mr Hyde by Robert Louis Stevenson. It is about a doctor who created a potion, splitting himself into two distinct personalities. He existed as the kind, gentle Dr. Jekyll, and the fearsome, malevolent Mr. Hyde.
If a player were to receive this random event underwater, Jekyll would be wearing diving gear.File:Aquajekyll.pngJekyll underwater!
Occasionally players will see Dr. Jekyll visit the Apothecary in Varrock.