Producers of the cult television series Lost say they are discussing the end of the series with US network ABC.
Lost follows plane crash survivors stranded on a desert island
Although the castaway drama is not set to finish in the near future, producers say they want an end date to help plan future episodes.
"Once we figure out when that will be, a lot of the questions will go away," said executive producer Carlton Cuse.
The third series of Lost, being shown on Sky in the UK, has seen viewing figures drop by more than a million.
In the US viewing figures have also fallen by around 14%, but the show's creators say the drop-off is deceptive because the programme was a "sensation" in its first two series.
However, they admit that they plan to finish on top, citing The X-Files as a comparable series which outstayed its welcome.
"That was a great show that probably ran two seasons too long," Cuse said. "That is a cautionary tale for us."
Lost has been a critical and commercial success on both sides of the Atlantic.
Set on a remote desert island, the show looks at how the survivors of a plane crash deal with their hostile and mysterious new surroundings.