When World War I broke out, Massonet served in the Belgian army as a stretcher-bearer, and during that time he also helped launch the illustrated newspaper *Le Claque à Fond*, a publication that came to symbolize the cultural life of Belgian soldiers on the front lines.

His work is characterized by a wide variety of subjects. He paints views of Brussels, Paris, and Venice, as well as interior scenes and portraits, but also compositions dedicated to music, theater, and dance.
His lively and spontaneous brushwork reveals a constant fascination with movement.

In addition to his work as a painter, Massonet created numerous posters and advertising illustrations. He worked for companies such as Philips, Agfa-Gevaert, and the Belgian National Railway Company (SNCB). His style is highly sought after by advertisers

After World War II, he spent time regularly in Paris, where he moved in the circle of Maurice de Vlaminck.
This period helped broaden his palette and strengthen the freedom of his painterly style. He then pursued a particularly active career, alternating between exhibitions, publications, and commissions.

With its vivid lines, immediately accessible composition, and ability to capture a pose in just a few strokes, this painting evokes the world of illustration, poster art, and even early comic books.
The theatrical lighting and the characters sketched from life reflect the sense of rapid storytelling that was the hallmark of his graphic work.