Poldark follows Downton Abbey gaffe with promo photo featuring modern burglar alarm

Beady-eyed viewers spotted the 21st century device in the backdrop of a shot

A burglar alarm can be seen in the background of this BBC Poldark press shot (BBC)

First it was the plastic water bottle in those Downton Abbey press shots and now, a distinctly 21st century-looking burglar alarm has been spotted in publicity images for new period drama Poldark.

Beady-eyed viewers drew attention to the modern object, which can be seen in the background of a BBC photo, despite the cast's costumes being clearly 18th century.

The offending alarm was removed by the show’s editing team before it aired on Sunday night to an audience of 7 million, becoming the highest-opening new drama since The Musketeers last year.

Viewers also noted that a lighthouse in the episode would not have existed during the time that Poldark is set, with others complaining about lead actor Aidan Turner's "unrealistic" scar resembling "a bit of mascara running down his face".

Despite this criticism, Poldark received a generally warm reception from reviewers and audiences. The story focuses on Captain Ross Poldark, who returns home to Cornwall after three years fighting in the American War of Independence, only to discover that his father his dead and his fiancée Elizabeth is engaged to his cousin.

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The original Seventies Poldark remains one of the BBC's most successful costume dramas ever, reaching 18 million viewers at its peak and coming second only to the 1995 adaptation of Pride and Prejudice (featuring *that* Colin Firth wet shirt scene).

To be fair, the device blended in to Poldark's backdrop much better than the aforementioned Downton bottle, which was accidentally left on a mantelpiece before the fifth season began.

Downton Abbey cast make light of the water bottle photo gaffe (Instagram)