Singing from the same song sheet! Gwen Stefani and Blake Shelton were in perfect harmony on Monday, May 9, when they debuted their duet, "Go Ahead and Break My Heart" during their hit music show, The Voice.

The couple, who have been dating in the fall and wrote the duet at the end of last year, took to the stage together, arm in arm, to prepare for the big performance, with Stefani looking totally sunning in a sheer, mermaid style gown that featured floral jewels throughout by Australian designer Jaime Lee.

Stefani, 46, waited in the wings while boyfriend Shelton, 39, took center stage with his guitar, ready to start his performance.

During the first take of the prerecorded segment, "Gwen sauntered out at the end of Blake's first verse and stood next to him for the rest of the performance," Us Weekly's insider reveals. "They faced each other and didn't look at the audience at all during the performance. It was like they were trying to give the illusion that to them, they were the only ones in the room. It was so romantic."

At the end of the performance, Shelton pulled his love into his arms, "and kissed her forehead."

The couple then did a retake of the performance, which was pretty much identical, other than they didn't kiss at the end. "Blake just put his arm around Gwen for a hug," our spy reveals.

It turned out that the duo chose the second take to broadcast during the hit music show, but despite missing out on the kiss, viewers were left in no doubt as to the affection the pair have for each other.

@blakeshelton @nbcthevoice #goaheadandbreakmyheart Gx

A photo posted by Gwen Stefani (@gwenstefani) on

After their performance, Stefani took to Instagram to share a number of photographs of her in her stunning outfit, and one adorable pic of the two of them together.

"@blakeshelton @nbcthevoice #goaheadandbreakmyheart Gx," she captioned the photo.

Watch the cute performance in the video above. 

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