By killing his best friend, Shisui Uchiha.
It is Uchiha Shisui's who is the guy that Itachi killed to get the last form of the sharingan.
because shisui was spying on itachi for the uchiha clan because the uchiha clan new that itachi was working with the leaf to try to overthrow the uchiha clan plus to get the mongekyou sharingan (you must kill your closest friend to obtain the mongekyou sharingan)
Yes, Sasuke Uchiha does have the Mangekyo Sharingan. He awakened it after the death of his brother, Itachi Uchiha. Sasuke's Mangekyo Sharingan has a unique design and grants him various powerful abilities.
Madara Uchiha, Izuna Uchiha, Itachi Uchiha, Kakashi Hatake, and Sasuke Uchiha. Madara and Izuna did not gain the Mangekyō Sharingan through the traditional methods, but through hard, extensive training with each other. Itachi killed Shisui Uchiha. Sasuke killed Itachi. Kakashi didn't kill anyone close to him, but he feels responsible for the deaths of Rin and Obito Uchiha. This gained him his Mangekyo Sharingan. It is also rumored that Naruto Uzumaki can use the Mangekyo Sharingan because Itachi gave Naruto some of his powers before he fought Sasuke but this is highly unlikely.
For those who are alive until shippuden it is Kakashi- Madara Uchiha- Sasuke Uchiha- Itachi Uchiha- Danzo
In short: born into the Uchiha clan, became friends with Itachi Uchiha, gained the Sharingan and Mangekyo Sharingan, was assign to spy on Itachi by the clan when they where planing a coup and Itachi was acting strange, tried to stop the coup and got one of his eyes stolen by Danzo, gave his other eye to Itachi and killed himself.
Sasuke Uchiha, Tobi AKA Obito Uchiha, Madara Uchiha, Shisui Uchiha, Kakashi Hatake, Danzo and Itachi Uchiha.
There are only a few known Naruto characters that posses the Sharingan. The first is Uchiha Madara. He and his brother Izuna are the first of the uchiha to obtain the Mangekyou Sharingan. The Second and third is Uchiha Itachi & Uchiha Sasuke. Next is Uchiha Obito. He gained his sharingan while on a mission with the soon-to-be Yondaime Hokage, 13 year old Kakashi and Rin but died shortly after. Kakashi and Danzo are the only known Non-Uchiha Sharingan users. Kakashi got is from Obito and Danzo stole it from the murdered Uchiha Shisui. Lastly is Uchiha Shisiu. Not much is known about him but it is common knowledge that he was murdered by Itachi to gain the Mangekyou.
His name is madara uchiha and he possesses the sharingan so his brothers are sasuke and itachi.
His name is madara uchiha and he possesses the sharingan so his brothers are sasuke and itachi.
the "Naruto" carachters that are capable of using the mangekyou sharingan are Sasuke Uchiha, his brother Itachi Uchiha, Madara Uchiha (Tobi in the Akatsuki Organization) and, in the past, his brother Izuna Uchiha. and, even though he is not part of the Uchiha clan, Kakashi Hatake, who received it from Obito Uchiha.
Itachi is the Uchiha who betrayed his clan. Because of that, he became missing-nin. He is partnered with Kisame, and can use Mangekyou Sharingan. He is killed by Sasuke.