Filming is currently underway for the soap's finale, which will air in Australia on Channel Seven in December.
Speaking to TV Soap, a Home and Away spokesperson said: "People are going to need to pay attention and be watching closely.
"This is one of the best cliffhangers we have ever attempted, and so much of the mystery will not be solved until early in 2010 when everything will be revealed."
In April, series producer Cameron Welsh promised fans that the unexpected outcome to the soap's year-long mystery storyline will "change Summer Bay forever".
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