Channel 4's new drama Lost pulled in ratings of more than six million for its first night.
The first episode of the much-hyped US show had an average audience of 6.1 million, which are the channel's highest figures for a US drama.
It's a much bigger figure than that for the first episode of Desperate Housewives, which drew 4.6 million for its initial show.
The first two episodes of the Lost (which were both screened in the same evening) were the highest-rating programmes in their timeslots.
And the programme was so popular that 1.5 million viewers tuned into a preview of next week's episode on digital channel E4.
The show deals with 48 disgruntled survivors of a plane crash on a mysterious tropical island.
The feature-length pilot episode cost £3m - the most expensive in history.
A Channel 4 spokesman said: "We are absolutely delighted with the huge success of those ratings. There is obviously a large appetite for innovative and distinctive quality drama."
