Anyone who’s been following updates on Thor: Ragnarok, Chris Hemsworth’s third solo outing as the Marvel superhero, will likely be aware that much of the film has been improvised (as much as 80% in fact, according to reports).

But the story behind one of the most iconic and memorable lines from what we’ve seen of the film so far – namely in the trailer – is actually very touching.

The line comes when Thor, who has been placed in a battlefield, finds that the opponent he’ll be facing is none other than fellow Avenger Hulk. Thor calls out “He’s a friend from work!” and so a beloved movie quote was born.

You can refresh your memory of it here:

 

As it turns out, the line actually comes from a child from the Make-A-Wish foundation. Hemsworth revealed to EW that the young boy was visiting the set during filming thanks to the charity.

“We had a young kid, a Make-A-Wish kid on set that day,” Hemsworth explains, “He goes, ‘You know, you should say, ‘He’s a friend from work!’” The actor was allowed to do a take with the line the kid wanted to hear and it worked perfectly.