Thoughts on, and a place to discuss, the plot points we can’t reveal in our review.
As fans of The Abyss have likely guessed, The Wave features the person who keeps administering CPR long after the victim has clearly died, who’s inevitably vindicated by a sudden gasp and the sight of the alleged corpse coughing up water. In this case, it’s teenager Sondre who saves Kristian, refusing to stop pumping Dad’s chest even after his mother sorrowfully tells him to let go. This device always feels cheap—Ed Harris only maybe just makes it play through sheer force of will, and he’s Ed fucking Harris—but the alternative, in which Kristian dies, would probably be too much. For one thing, he would have died by giving Sondre literally his last breath, as he drowns because Sondre was drowning and Kristian transferred the remaining air in his lungs to get him to safety. Now imagine coping with that guilt after you’ve also watched your mother kill somebody to save your life. The whole reason Sondre nearly didn’t make it out is that he’d already been held underwater at length by Thomas Bo Larsen’s hotel guest (not out of malice, just sheer blind panic), forcing Idun to deliberately drown the guy; it’s a genuinely disturbing scene, with Idun calmly telling the horrified Sondre not to look as she uses her legs, wrapped around the guest’s neck, to pin him beneath the surface until he finally stops struggling. When Sondre subsequently refuses to accept his father’s death, it’s arguably because he’s unconsciously aware that a second trauma of that magnitude, hard on the heels of the first, would wreck him for life.