Saul Dreier, 89, and Reuwen “Ruby” Sosnowicz, 85, rehearsing in their hotel suite in Las Vegas in 2014. (Louis Lazar)

If you need a pick-me-up for the day, try the New York Times‘ latest Op-Docs feature, a five-minute video about Saul Dreier, 89, and Reuwen “Ruby” Sosnowicz, 85, two Holocaust survivors in Florida who last year started a band called, simply, Holocaust Survivor Band (its official name is Holocaust Survivor Klezmer and Multicultural Band).

Louie Lazar profiled the duo back in December for Tablet, when they played a show at the Venetian Resort Hotel Casino in Las Vegas with singer Dudu Fisher. Dreier, a Krakow native who plays the drums, survived Mauthausen and two other Nazi concentration camps. Sosnowicz, who plays the keyboard and accordion, was born in Warsaw and went into hiding after escaping the Warsaw Ghetto.

“When we heard music, it made us alive,” said Sosnowicz of his wartime experiences. The two also note that their music reminds other Jewish seniors of their childhoods.

The video shows the spritely older gentlemen singing and playing Jewish classics like “Hava Nagila” and Fiddler on the Roof’s “To Life.” They frequently play for large audiences of their peers—including many older Jewish women (no official word on groupies, but Sosnowicz does mention being asked often if he’s single). Throughout, when they play, they are positively beaming.

Related: The Holocaust Survivor Klezmer and Multicultural Band Does Las Vegas