The Silver Hand

Background
''I have ascended to the Circle which leads the Companions, and now share their blood as a Werewolf. To celebrate my new status, Skjor and Aela have invited me to attack a Silver Hand camp nearby.''

Walkthrough
This quest allows the Dragonborn to become a Werewolf. Becoming a Werewolf increases health and is reversible.

To start this quest, the Dragonborn must either speak to a Companion, or go to Farkas, and ask him for a job. He will then direct him/her to see Skjor. Skjor will insist him/her to meet him at the Underforge at night. There’s a pretty clear outline along the rock wall that indicates where the secret entrance is. He/She then must head inside the Underforge, and when ready tell Skjor to begin the ritual. After the ritual, the Dragonborn has moved out into Whiterun, and everyone is alerted. He/She must wait for the effects to wear off or wait until the health bar is depleted, upon which he/she is knocked unconscious. Also, if you choose, you can slay any number of NPCs and feed on them. You will accrue no bounty for anyone murdered during this first transformation. (There may be a difference from this description in the PC version, or an update has changed this; upon transformation, the Dragonborn is still in the underforge and can exit to the city proper, or use the one-way exit to the countryside to the East of Whiterun.) Map, inventory, and most other actions are not available while in Beast form, but the experience will persist, so map points discovered and foes killed will be there once back in normal form.) Upon regaining consciousness, the Dragonborn will have already reverted to human form, although he/she can transform into a Werewolf by selecting Beast Form under Powers in the Magic menu (keep in mind that there is a cooldown period).

Aela mentions a Silver Hand camp nearby that must be exterminated. There is no specific way this "dungeon clearing" must be accomplished. Aela will be your follower during this part of the quest.

A straightforward approach is to head into the stone bunker at Gallows Rock, pull the chain to lower the gate, and proceed through the passages and rooms to the leader, Krev the Skinner. Note that there is a door that cannot be opened because it is barred from the other side - the Dragonborn must proceed through the rest of the dungeon bearing to the right. In the fight, Krev is accompanied by three archers; taking them out first will allow attacks to be focused on Krev to dispatch him/her. At lower levels, Krev will also be susceptible to the fear-inducing roar while in Werewolf form, which can turn the battle in a mere farce.

Speak to Aela afterward to finish the quest.

Followers
If the Dragonborn has a follower, the follower will not be present when the former regains consciousness after being a werewolf for the first time. This is because Aela automatically becomes his/her follower from this time until the end of the quest. The Dragonborn's original follower will return to the place where he/she first met him or her. (Also, telling the follower to wait in a place before the Dragonborn start the quest will not prevent him/her from returning to the place where you first met him/her.)

Bugs
Die Silberne Hand La mano de plata La Mano d'Argento "Серебряная рука" (Квест)