“The Undoing” executive producer and director Susanne Bier says a test audience for the HBO limited series hoped to see Hugh Grant’s Jonathan Fraser reunite with his wife Grace, played by Nicole Kidman.

It is a sentiment Grant himself shared with Variety that his real-life wife had while reviewing the material, as well. But in the final episode of the six-part adaptation of Jean Hanff Korelitz’s novel “You Should Have Known,” Grant’s Jonathan was revealed to be the one who murdered his mistress Elena (Matilda De Angelis). If that rage-filled action wasn’t enough to make viewers think twice about Jonathan deserving to keep his family intact, he then went and kidnapped his son Henry (Noah Jupe).

The finale culminates in an increasingly tense sequence in which Jonathan speeds toward the Kingston–Port Ewen Suspension Bridge with his young, nervous son in the passenger seat beside him, while Grace and her father (Donald Sutherland) chase them in a helicopter. When they reach the bridge, Jonathan threatens to jump.

“They rigged a basket for me to fall into, should I fall in,” says Grant. “I was much more worried about the acting side of it because you have to keep it real.”

Although filming of “The Undoing” took part over some cold months in New York, by the time they had gotten to this sequence, it was a hot and humid day. “We’d have to hide in that car in between takes because it was 100-degrees,” he reveals.

During the scene, both Grace and Henry scream at Jonathan, pleading with him not to jump.

“By the end of that scene Nicole and Noah had lost their voices because he was screaming and Nicole was screaming,” says Bier.

Bier explains that in the moment Grace comes running toward him, he believed there would be redemption for him.

“Jonathan believes that Grace has come to her sense wanting to save him,” she says, adding she hoped the audience would respond with, “No, she’s not going to do that.”

Despite numerous conversations about whether Grace would go back to him as he was about to be captured, Bier says, that would never have happened.

Watch Bier and Grant break down the full scene in the video above.