Telly bosses are delighted that the latest series of the Inspector Morse spin-off Lewis drew impressive Sunday night viewing figures.

About eight million people watched each of the four episodes, which finished on Sunday, and the large audience share on each night makes it likely new films will be recommissioned.

The first episode, And the Moonbeams Kiss the Sea, got eight million viewers, a 35 per cent audience share, Music to Die For got 7.7m, a 35 per cent share, Life Born of Fire got 7.5m, a 33 per cent share, while The Great and the Good got eight million viewers, a 35 per cent share.

ITV spokesman Lisa Vanoli said: "We can't comment on recommissions at this stage, but ITV is really pleased with the consistently high viewing figures that Lewis got."

ITV screened a pilot episode of Lewis in January, 2006, and it won 11.4 million viewers - making it the most watched drama of the year across all channels.

Further episodes of Lewis were shown in February and March last year and the viewing figures were healthy enough to merit a second series, which was shot on location in Oxford last autumn.

Paul Allen, whose book Endeavouring to Crack the Morse Code, details locations used in Morse films, said: "These viewing figures are stunning and The Great and the Good, the last film of the four, was as good as anything in the Morse series.

"Kevin Whately as Lewis, and Laurence Fox as DS Hathaway, are developing a fantastic on-screen rapport, and at the end of the series the door was certainly left open for further episodes.

"There was no indication that either of them was ready to retire and I'm convinced that the Lewis film crew will soon be back on the streets of Oxford.

"Lewis was up against a drama series on BBC1, The Last Enemy, which got good reviews, but everyone I spoke to said they switched over to Lewis as soon as the series started."

Last month, it emerged that Lewis was the first ITV drama show for which producers calculated a carbon footprint.

In a bid to reduce greenhouse gases, those taking part in the shoot shared vehicles and read scripts on recycled paper, and the carbon footprint for the series was calculated as 830 tonnes.

John Thaw, who played Inspector Morse, died of cancer in February, 2002, two years after the last episode, The Remorseful Day, was screened.

Many of the Morse episodes were based on stories written by Oxford-based author Colin Dexter, who has been given cameo roles in the dramas.

Morse episodes often had high viewing figures in the UK, with a peak of 18 million for episodes in the mid-1990s.