Hirokazu Ukita is the most emotional of the Kira investigation team that is lead by L. When Misa Amane has Sakura TV broadcast a message from her as Kira, Ukita rushes to the station to stop the broadcast, without any prompting by the rest of the team. Since Misa has the Shinigami Eyes, she kills him as soon as he approaches the door and is about to shoot. He is voiced by Hidenobu Kiuchi in the Japanese anime and Jeremy From in the English dub. In the film, he is portrayed by Ikuji Nakamura, and appears notably older. Ukita does not die in the film.
Hideki Ide is one of the few police officers who remains with Soichiro during the Kira Investigation. He initially leaves when he disagrees with L's methods. Ide later returns and plays a relatively minor role in the Kira investigative team. He helps coordinate their efforts, and performs actions such as organizing a blockade of police cars to trap Higuchi. Later, after L's death, he rejoins the investigation, though he states that he only did so to be with Aizawa. Ide trusts Light more than any of the other Task Force members, except for Light's father.
Clear Note is the main mamodo antagonist of the King Festival arc of Zatch Bell!. After Gash defeated his brother, Zeon, he gave Gash a letter that revealed that there was an evil power even greater than his still out there. Shortly after the King Festival began, Gash was confronted by Ashuron, one of the finalists, who revealed that this evil was Clear Note, one of the remaining mamodo. Clear compares himself to a nuclear bomb and wishes to erase both the Mamodo World and the Earth World. His main power is Annihilation. (Source: ZatchBell Wiki and Wikipedia)
Stephen works for Near as part of his investigation team, along with Lidner and Rester, and later plays an important role in stopping Kira. When suspicions arise towards Mikami, Near assigns Gevanni the task of following him, studying his methodic lifestyle, and finding his connections to the Death Note. Before the final showdown with Light at the warehouse, Near has Gevanni steal both the fake and real Death Notes from Mikami, and tampers one of the fake's pages. He also creates another fake, replacing the real one, that is later used as Light's ultimate downfall, and ends up being Near's key to proving Light's identity as Kira. While looking for the SPK members' real names, Mikami views his real name as Stephen Loud through his Shinigami Eyes. In the one-shot chapter set three years after Light's death, while he didn't have any speaking lines and much any involvement in the short story, he did appear in one panel alongside Rester and Lidner. This suggests that he may still be working with them under the new L, Near *Wiki