When the apprentices leave the camp to become warriors, the Shadowclan attacks their den. The apprentices return with the deputy warrior and the leader of the clan Bluestar and engage in the battle. During the battle the deputy warrior, Lionheart, was killed.
When the kits get captured Firepaw and his friends go looking for them and find out that the Shadowclan has taken them.
Firepaw and Graypaw become warriors after the kits are safely returned back to the camp. The Thunderclan held a ceremony to celebrate.