(ET ONLINE) — Chris Evans knows how to liven up a party!

While Avengers: Endgame was claiming the top spot for the second weekend in a row (and breaking tons of records along the way), one of film’s leading men was surprising former classmates at a high school reunion!

The 37-year-old actor was spotted mingling at the Lincoln-Sudbury Regional High School 20-year reunion at Conrad’s Restaurant in Boston, Massachusetts, on Saturday, May 4.

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