A restless photographer leaves her family to "find herself" and takes up deep-sea diving.
César is a 40-year-old French journalist who has witnessed a Tsunami in the Indian Ocean and suffered kidnapping in Lebanon. Having had enough adventure in his life, he returns to settle down to a quiet life back in Paris where he becomes a culture writer. His real focus though becomes Paz Aguilera, a younger passionate photographer from Asturias, Spain with a fascination for sharks of which eventually she adopts one that she follows online with GPS.
César meets Paz in an art show and the two fall in love. The two have a whirlwind frolicking romance where they act out their love and after an early honeymoon Paz quickly becomes pregnant. Now living in César's dreary apartment in Paris, the artsy free-thinking Paz clearly cannot come to terms with being pregnant and is obviously unhappy living in the old continent; soon domestic troubles ensue. César clearly cannot understand Paz's depression and suffering.
The baby is finally born and despite her attempts to relieve the pressure of being a new mother by riding the metro in circles for hours, or taking fragmented portraits of herself, as well as following her adopted shark online through GPS, she clearly is not coping well with her new role, something that César really has problems understanding. Their relationship is breaking apart from the inside in slow-motion as César tries to shout some sense back into her.
After getting a friend of César to help her mount an art exhibition of her work at the Louvre Museum, the highlight of her career, she announces to an incredulous César that she is leaving him and Hector, the baby, because she needs time and distance to find herself. While César has problems rising to the challenge, his whole life caves in when he receives the news that the naked deceased body of Paz was found on a beach on Oman. Leaving Hector behind, temporarily in the care of another, César flies to Oman to try and understand what had happened.
In Oman, César recognizes the body and tries to investigate her death. César is clearly mourning her loss and seems himself at a total loss to understand her. Initially, he finds uncooperative witnesses on the beach where her body had been found but eventually he finds someone who informs him that Paz had been an avid diver (plonger in French) in a diving club nearby. Pursuing the lead he meets a woman who was a friend of Paz but who tells him little at first as he does not reveal his true relationship to Paz. César also joins the diving club and begins to take instruction from Marin, Paz's former dive instructor as we later find out, in an effort to both learn more about what had happened to his wife Paz, and to try and understand who she really was and why she had abandoned her family to come to Oman.
Initially, Marin does not acknowledge that he knew Paz. In another encounter with the woman who was a friend of Paz, César reveals to her that Paz had left her baby behind in Paris with him, Paz's husband, something the woman did not know. Realizing that César deserved to know more about Paz and her life in Oman, she reveals that Paz seemed to spend all of her time diving with her instructor Marin right up until she died.
Armed with this information, César confronts Marin and learns that indeed Paz and Marin had gone out to dive on the night of her death. César demands to know what exactly had happened that led to Paz death. Marin, in an emotional confrontation, admits that Paz had not only obsessed over diving in the deep where it seemed to be the only place she felt calm and at peace deep down under the blue waters of the sea, but also she had obsessed over a fascination with sharks.
On the fateful night, Paz had insisted that Marin take her to dive at night in a location where a known shark was she wanted to encounter. He complied and explained that he had witnessed Paz's flashlight fall by itself to the depths of the ocean just after she had plunged into the sea. He dragged her dead body back into the boat and explained that he did not know the exact cause of her death, perhaps a problem with the air mixture in the air tank she was wearing, perhaps an air bubble in her bloodstream. Marin then explains that he took her body to another location and left her naked body floating in the water to be found by others. He admitted that he had failed to report the death for fear that authorities would close the diving club, the source of his livelihood.
César, visibly upset, insists that Marin take him to the spot where his wife Paz had dived on that fateful night when she died. Marin accepts to take him and in the final scenes, we see Marin and César floating slowly in the depths of the sea around a large gray shark which remains mostly immobile as César slowly makes physical contact with it by touching it with his hand while Marin looks on. Returning to the boat that they had arrived in, César has flashbacks to better times when his wife and he had met and fallen in love with each other. There seems little else that César can now learn about Paz and what drove her psychology in this heavy-handed story of mourning and loss, however, his understanding has come too late.
Credits roll.
