The unsuspecting Sutherland, a Peabody educator for the past 37 years, walked right past them into the cafeteria, and when he grabbed his tray, they followed him in and struck.
After their Outkast performance, they trailed the professor to the table where Bryn-Julson sat and lit into their second number, Sonny and Cher's "I Got You Babe."
"Don't let them say your hair's too long, 'cause I don't care, with you I can't go wrong," the ladies sang, holding each other's hands as their bandmates "doo-wopped" in the background.
The couple, married 44 years, beamed, their arms around each other, and sang along. At the final notes, the cafeteria burst into applause.
The Valentonez gathered their gear and got ready to head to their next stop, a place in Ridgely's Delight. After that, there would be a half-dozen more, then another spate on Valentine's Day.
But the effects of their performance lingered.
"I got my money's worth. Their phrasing was spectacular," said Bryn-Julson, an internationally renowned voice teacher.
Then she looked away, and her husband declared himself inspired.
"This reminds me to go buy a card," he said.