The Red Sea, circled by desert landscapes, is home to marine life accustomed to the water’s bathtub-like temperatures—often reaching 85 to 90 degrees Fahrenheit in the summer. But in the past three years, marine heat waves have made the Red Sea even hotter. It’s not turning out to be the safe haven we thought it was.”To a clownfish, anemone bleaching is a catastrophe—their once safe home turns white, exposing them to dangers lurking in the surrounding reef. Human-caused climate change has heated the ocean to new extremes, and has started to unravel the mutualistic relationships that sustain underwater environments, like those between algae and corals, algae and anemones, and anemones and clownfish. The authors call for surveys in other regions of the Red Sea, as well as worldwide, to evaluate their conservation status at large.