Researchers were investigating a mural painted by Italian artist Vasari in Florence, Italy last year.

They had a hunch that on a wall behind Vasari’s mural, another mural might be lurking — one painted by the famous Italian artist Leonardo da Vinci.

The researchers were right.

They put a probe with a camera on it through the first mural.

Underneath, they found the Leonardo painting, The Battle of Anghiari.

The research team was led by scientist Maurizio Seracini and included specialists from the National Geographic Society, several universities and the City of Florence.