Items Needed: Rat Meat, Bear Meat, Cow Meat, Chicken Meat and some good Armour (maybe Food).

Start: North of Taverley, Druids' Circle; talk to Kaqemeex.

1. Walk to the Herblore Shop, go up the Steps and talk to Sanfew, tell him you've been sent to assist him with the Ritual to purify the Varrockian Stone Circle.
2. Sanfew will tell you he needs Meats, so get the four Animal Meats. Head to Lumbridge, kill a Cow, then a Chicken. Take the northeast Path into Varrock, kill a Bear along the way, and take its Meat. Head to the Sewers, kill a Rat (a big one) grab its Meat.
3. Head to Taverley, south of the Herblore Shop and you'll see a ( ! ) standing on your Map. Go there and proceed down the Ladder. Walk straight north until you reach two Suits of Armour, click on the Prison Door Gate. The Suits of Armour will Attack you, kill them both. Use all four Meats with the Cauldron of Thunder and they will turn Light Blue.
4. Return the four Light Blue Meats to Sanfew, he'll tell you to talk to Kaqemeex and he will authorize you to use Herblore.
5. Talk to Kaqemeex and retrieve your Reward.

Congratulations, Quest Complete!

Reward: 4 Quest Points and 250 Herblore Experience