Gotye performs at Merriweather Post Pavilion this weekend. (Carlo Allegri/Reuters)

The show is one of the items our list of the 21 best things to do in the D.C. area this weekend. Also featured:

• On Saturday, the outfield normally patrolled by Jayson Werth and Bryce Harper will be overrun by lawn chairs, picnic blankets and opera lovers. For Opera in the Outfield, the big center field scoreboard will show a live stream of the Washington National Opera performing Mozart’s melodrama “Don Giovanni.” Gates open at 5 p.m. for pre-show activities and entertainment, including stage-fighting demonstrations and flamenco dancing.

• If you’ve ever wanted to go green, you can spend this weekend at the DC Green Festival, which features DIY demonstrations, a green film festival, speakers, workshops and a marketplace, all under one roof.