They’ve been there from the beginning, and now they have matching ink to make their connection in protecting the world, or the Marvel Cinematic Universe, permanent.

Five of the six Avengers took a page out of the “The Lord of the Rings” playbook and got matching tattoos.

Robert Downey Jr. said it was all Scarlett Johansson’s idea.

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"She and (Chris) Evans did it in New York. Then their New York guy, Josh Lord, who is amazing, flew out to LA, he did me, did (Jeremy) Renner, and then we just bullied (Chris) Hemsworth into doing it, and he got it," Downey told Entertainment Weekly.

The only one not to be part of the tattoo group was Mark Ruffalo.

But the there was a sixth person in the tattoo chair -- the artist himself -- who had each of the five Avengers stars make a line on his version of the stylized Avengers symbol.

"Each of us contributed to giving the tattoo artist the sixth tattoo that he designed for us. By the way, he's got another one on him that Scarlett did, which is beautiful, which is crazy, because the line she drew on him, which was supposed to be a straight line, looked like a lightning bolt. It was a mess," Downey told Entertainment Weekly.

The "Avengers" cast isn't the only one to get the same ink after filming was complete. The cast of "The Lord of the Rings" also got matching tattoos more than 10 years ago of the number nine written in elvish. Even Sir Ian McKellen and Sean Bean got into the act, to mark the end of the epic trilogy, Entertainment Weekly reported.

"Avengers: Infinity War" has made more than $1 billion in theaters so far, The Washington Post reported.

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The History of Marvel Comics and the Marvel Cinematic Universe