The cause of the problem was not 'immediately' clear. [=is was not known right away]
They live in the house 'immediately' [='directly'] behind this one.
We need to leave 'immediately'. [='at once', 'right away']
(..) and fully grown men? No. Ebrose: Maester Cressen discovered Shireen Baratheon's affliction immediately. This is quite advanced. And beyond our skills, ser. Were you a commoner, I'd have you shipped to Valyria at once (..)2017 TvShow: Game of Thrones Title: Stormborn Season: 7 Episode 2