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 why do you think you're here talking to me? These people don't make mistakes. What's wrong? Salt Lake City, Utah. Transfer effective immediately. I already gave Skinner my letter of resignation. You can't quit now. I can, Mulder. I debated whether to tell you in person... (..)1998 The X Files
(..) - The morgue. That area's currently off limits. - On whose orders? - General McAddie. We were woken at am and told to get down here immediately. I don't know about that. - Call General McAddie. - I don't have the number. Call the switchboard. You don't know their number? (..)1998 The X Files