The Beach Boys perform at Merriweather Post Pavilion as part of the band's 50th Anniversary Reunion Tour. This tour marks the first time chief songwriter Brian Wilson has done a full range of dates with the band since 1965. (Kyle Gustafson/For the Washington Post)

Nostalgia acts don’t come any more nostalgic than the Beach Boys.

Their tour, which stopped at Merriweather Post Pavilion for a well-attended concert Friday night, commemorates the 50th summer of their perennial Southern California adolescence. Their average age? Sixty-eight.

In their ball caps and billowy shirts, they look like golfers, not surfers. None of them has the unlikely physical vitality of fellow sexagenarians Mick Jagger or Bruce Springsteen. But bolstered by nine additional singers and musicians, they matched their contemporaries’ generosity, performing two sets that added up to four dozen songs in 2 1 / hours.

Ageless hits (along with some emphatic gesturing by Beach Boy Bruce Johnston) brought the audience regularly to its feet, but the long set list allowed room for some welcome visits to the weirder, more interior corners of the Beach Boys songbook, too (and to “Kokomo,” unfortunately). The return of Brian Wilson, the troubled genius whose health problems have often prevented him from touring, made this outing feel significant. Although Wilson was a grim presence, hunkered unsmiling over his piano, his vocals on lonely songs such as the alienation anthem “In My Room” and the spacey “Sail On, Sailor” were the antidote to his cousin Mike Love’s embarrassing-uncle banter.

Films of the group in their prime played on a giant mock-up of a console-style TV set behind the bandstand, where those additional players used a flute, a theremin, a vibraphone and a variety of percussion instruments to conjure the studio-honed perfection of the recordings. Still, the way four generations of faces in the audience lighted up during “Good Vibrations” and “Fun, Fun, Fun” was enough to melt away cynicism, like the warm California sun.

Klimek is a freelance writer.