The touching moment that was improvised on the set of 'Ford v Ferrari' (exclusive)

Despite having a great script, sometimes the best movie moments are conceived right on the spot.

Take, for instance, one particular sequence in the Oscar-nominated drama Ford v Ferrari, as revealed on the film's upcoming home entertainment release (watch exclusively above).

The scene comes early on, as driver Ken Miles (Christian Bale) triumphs during a race at Willow Springs while his son, Peter (Noah Jupe), watches from the sidelines.

20th Century Fox

"One of the first takes we did, Christian drove up and he had a line exchange as he drove by his son," explained director James Mangold. "And [Christian] said to me, 'Why wouldn't I just ask him to get in with me?' And I said, 'Why not? Let's try it.'"

Furthermore, Bale had the idea to have the two of them then sing a song he knew from his childhood in England, the nursery rhyme "I'm H-A-P-P-Y" — which Jupe, having also grown up in the U.K., knew as well.

"It was such a beautiful moment," said Mangold.

Ford v Ferrari arrives Jan. 28 on digital services and Feb. 11 on 4K Ultra HD, Blu-ray, and DVD. Steelbook exclusively available at Best Buy in 4k Ultra HD/Blu-ray.

Watch Christian Bale and Matt Damon talk about filming the movie's wrestling scene:

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