There are many eye-catching flowers in the world, but here's an exception: Diphylleia grayi, the so-called "skeleton flower." It's not that it's not beautiful; your eye just might miss it on account that it turns transparent when it rains.
Normally, this delicate bloom is an opaque white color, but when the rain begins to fall, it turns crystal clear. The white veins in the petals appear like bones, thus the ghoulish moniker. When the flower dries off, it goes right back to being white again. It works in a way that's similar to the concept at play in a wet T-shirt contests, in which contestants wear white shirts that become more transparent when drenched with water.
Skeleton flowers are native to wooded mountainsides in the colder regions of Japan, and they bloom from mid-spring to early-summer in shady conditions. The plant might be easier to spot if you look for its large, umbrella-shaped leaves. The pearly white (or clear, if it's raining) blossoms top the leaves in small clusters.
You can see just how stark the contrast is between a dry Diphylleia grayi and a wet one in this following video, compiled by GeoBeats:
The ghost-like quality of these resplendent blooms certainly make them a remarkable find for flower hunters. But you may not need to brave the cold mountainsides of Japan to get a hint of what they might look like in person. A related species, Diphylleia cymosa, can be found in the deciduous forests of the Appalachian Mountains here in the United States.