Two hundred years ago, someone—an aspiring art conservator, perhaps—took a brush and coated a 1618 oil painting of a lady in red with a thick coat of ostensibly protective varnish. Over the decades, the varnish naturally discolored, turning first yellow and then brown, until the whole painting appeared covered in grime. Now—in a flourish—those two centuries of discoloration are gone.

Philip Mould is an art dealer and presenter on the popular BBC art program Fake or Fortune. He bought this painting at auction and posted videos of the dramatic conservation process as it happened. In the videos, Mould applies a substance—a gel-solvent mixture—to the surface of the painting, works it in, and then wipes it back to reveal the painting in its near-original glory.

The application of the solvent mixture appears to be slapdash, but that is the result of a great deal of testing, skill, and precision. Experienced conservators test their solvents so they know how they will affect a painting, and know just how much to apply and how long to leave it on. Too much, too long can damage the the paint, while a more cautious hand would have produced far less theatrical results.* The process can go wrong sometimes, even in the hands of experienced conservators.

The next challenge, Mould said on social media, is working out the story behind the paint. An inscription on the painting gives its date and the age of the sitter—36—but not who she is. But there are iconographic clues in her dress, Mould said, and his Twitter followers have been keen to suggest potential lookalikes, including Lucy Russell, Countess of Bedford.

* Update: A number of people have written in to say that Mould’s cavalier approach could result in damage to the painting.