recently, you've been acting stranger much colder and distant even to him. You've also been disappearing more often for these so-called 'missions' by the Hokage to get information about the coup d'etat from the Uchiha clan, but soon enough, he found out that was not true. Shisui would soon find the horrifying truth

Here you stand in Danzo's root uniform with your sharingan active. Shisui was horrified. He knew this wasn't you

"What has happened to you, Itachi?"