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']
(..) Dialogue: Marked=..,Default,NTP,!Effect,l'm afraid Professor Dumbledore is not here. Dialogue: Marked=..,Default,NTP,!Effect,He received an urgent owl from the\NMinistry of Magic and left immediately for London. Dialogue: Marked=..,Default,NTP,!Effect,He's gone? Now?\NBut this is important! (..)2001 Harry Potter and the Sorcerer's Stone