The team, assisted by art historian Bendor Grosvenor in series 1 to 5,[6] and professor Aviva Burnstock, Head of the Department of Conservation and Technology at The Courtauld Institute of Art, in later series,[7] investigate the paintings on a number of fronts: establishing the provenance of the piece by working backwards from present day to the time of the work's creation; on a forensic level, with investigation and scientific tests on the materials used to help establish specific time frames; and examining the unique painting styles and quirks of the artist.

Philip Mould was stated to have considered the Series 4 case of a Churchill painting as one of the most unsatisfactory endings to date, before it was finally authenticated in 2020.

[23] Philip Mould described the appearance on Swedish television weeks ahead of the British premiere as a "weird BBC World cock-up".

[25] Charles Henty seeks to validate the provenance of two inherited paintings, one by Alfred Munnings and one by Winston Churchill, discovered in a coal hole of a house in Ebury Street.

The team try to discover how the sculpture was acquired by the current owner's family, and although some promising leads are followed, there is no clear trail of evidence linking the piece to Giacometti himself.

However, the team learn that British artist Sidney John Woods was the original owner of a genuine 'Gazing Head' plaster.

The Coronavirus pandemic disrupted the production schedule, but in September 2020, Philip Mould announced that pre-production of the ninth series had started.

[58] Describing the outcome of the first episode of series one as a "scandal", Sam Wollaston writing for The Guardian found the programme "incredibly interesting" and praised it "for being about just one case in which you can become totally involved, instead of flitting between three, which is what so many documentaries seem to do".

[71] In The Daily Telegraph, Ceri Radford was described as being "flabbergasted" at the result of the first episode, but concluded her review by saying: "This may have been a disappointing finale, but it at least confirmed that this aesthetically pleasing, quietly enjoyable new series isn't afraid to thwart expectations.

"[12] Tom Sutcliffe in The Independent had a mixed view as a result of the presentation of the facts, saying: "It was full of cliffhanger tension and thrilling moments of discovery.

[75] Reviewing an episode of the seventh series, Michael Hogan of The Daily Telegraph wrote: "Arts programming is an increasingly endangered beast on prime time television.

"[76] Benji Wilson, writing for The Daily Telegraph, described the programme, then in its ninth series, as "the art world's answer to Line of Duty".