 He is captured and imprisoned in a cave by a terrorist group called the Ten Rings.Yinsen, a fellow captive doctor, implants an electromagnet into Stark's chest to keep the shrapnel shards that wounded him from reaching his heart and killing him.Ten Rings leader Raza offers Stark freedom in exchange for building a Jericho missile for the group, but he and Yinsen know that Raza will not keep his word.