This is a very neat low-lying plant with tidy leaves and tidy flower upright clusters. It’s also called the Pachysandra Terminalis Sieboldi. et Zucc. and also known as the Japanese Spurge.
The Pachysandra Terminalis is is an indigenous plant from the Boxwood family that is native in Japan and this one is kept by the garden of the Noh Theater platform near my house.
The flowers are in bloom as you can see. After the white blossoms, white berries follow. This plant is said to be one of the best plants for groundcover in shaded gardens. See link to the Pocketgardener for more info