Miranda Lambert fans in London got an extra special surprise at her show on Wednesday night (Aug. 23). Lambert brought her boyfriend, singer-songwriter Anderson East, to the stage to join her for a stripped-down duet on "Getaway Driver."

In the fan-shot video above, East and Lambert dismiss the rest of her band from the stage and he accompanies the duet on acoustic guitar as they join their voices in perfect harmony for the song, which they co-wrote with Natalie Hemby for Lambert's blockbuster double album The Weight of These Wings.

"So I keep the engine running / She'll be my gasoline / She treats my heart like a stolen car / All the while she's got the keys," they sing to the hushed audience in a spellbinding musical moment. "Standing in the line of fire / I'll be right beside her / I'm her getaway driver."

Lambert performed at London's Eventim Apollo Hammersmith Wednesday night as part of her ongoing Highway Vagabond Tour. According to Entertainment Focus in London, her set also included "Fastest Girl in Town," "We Should Be Friends," "Vice," "Ugly Lights," "The House That Built Me" and more hits, as well as a cover of Rodney Crowell's "I Ain't Livin' Long Like This."

Lambert turned to Instagram to gush about the performance afterward, writing, "London, England! Thank you so much. What an amazing night. And I got to sing a song with my 💗 @andersoneast," adding the hashtag #getawaydriver and others.

Lambert and East also shared a duet on The Weight of These Wings called "Pushin' Time" and co-wrote another song titled "Well-Rested," and they've collaborated on stage a number of other times at each other's live shows.

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