Even the most focused of stage actors can be rattled by an unexpected intrusion, such as an errant ringtone or overzealous audience murmuring. But a helicopter whirring past the stage? That’s fairly unique to 2020.

Yet E. Faye Butler was unfazed during Arena’s Stage outdoor production this week of “Fannie Lou Hamer, Speak on It!,” in which she plays the titular voting rights activist. As the chopper above the Wharf’s Transit Pier Floating Stage threatened to overwhelm Butler’s voice, her brassy bravado still pierced the autumn air with clarity.

The roughly 40 spectators — plus any passersby or Shake Shack patrons sneaking a glimpse — were all the better for it. The play’s week-long run of free performances, which concludes tonight, marked Arena Stage’s first foray into live theater since the coronavirus pandemic plunged the arts community into uncertainty in March.

An abridged version of Cheryl L. West’s play “Fannie,” this production was a fitting way for Arena Stage to dip a toe back into theatrical waters. (The full play is scheduled to make its world premiere at Chicago’s Goodman Theatre in 2021.) Directed with unfussy efficiency by Henry Godinez and grounded by Butler’s magnetic performance, “Fannie Lou Hamer, Speak on It!” makes for a stirring call to action as Election Day looms, in a world where the very circumstances of the production — outdoors, socially distanced, masks required — speaks to the urgency of its themes.

“To Hope is to Vote” sign in tow, Butler’s Hamer introduces herself with the real-life figure’s famed slogan: “I’m sick and tired of being sick and tired.” The play presents itself as a time-transcending sermon of sorts, as Hamer addresses the modern audience through the gaze of her civil rights era perspective. Over the next 50 minutes, the character takes indifference to task with blistering monologues and soulful musical interludes.

Music director Felton Offard contributes sharp guitar riffs and bluesy harmonica chords as a one-man backup band, separated from Butler by a plexiglass partition. Butler’s rich vocals and committed physicality carry the emotional burden as she belts out such protest anthems as “Ain’t Gonna Let Nobody Turn Me ’Round” and “We Shall Not Be Moved.”

But Butler’s performance is not all rousing righteousness. The play pivots from rallying cry to tears of rage as Hamer recalls the crippling beating she suffered after being unjustly tossed in a Mississippi jail cell in 1963. Meeting at the confluence of bravery and fear, Butler imbues her plucky protagonist with stark vulnerability.

As Hamer ruminates on the problems of the 1960s — police brutality, victim blaming, gentrification, the education gap and voter suppression, among them — the unsettling parallels to life in 2020 deepen. Even before the play evokes Harriet Tubman and John Lewis, the message crystallizes: If these heroes fought for what’s right in the face of unspeakable turmoil and trauma, what’s your excuse for apathy?

It’s unclear when the next Arena Stage production will hit the stage. But if this is all we see from the Southwest Washington theater for a while, give the company credit: Not content to sit back and wait for better times, Arena Stage made its voice heard.

Fannie Lou would be proud.

Fannie Lou Hamer, Speak on It!, by Cheryl L. West. Directed by Henry Godinez. Costumes, Joseph Salasovich; props, Jenn Sheetz; sound, David Naugton. Through Friday at the Transit Pier Floating Stage at the Wharf, 960 Wharf St. SW. The show is sold out, but a limited number of standing-room tickets are available and can be reserved online at arenastage.org.