Camissonia contorta is a species of evening primrose known by the common name plains evening primrose. It is native to western North America from British Columbia to California to Idaho, where it grows in many habitat types. It is an annual herb producing a slender, bending to curling red or green stem which is sometimes hairy. It is up to 30 centimeters long and erect or spreading out. The blue-green leaves are linear to very narrowly oval in shape and up to 3.5 centimeters long. The nodding inflorescence produces one or more small flowers. Each has bright yellow petals up to half a centimeter long, sometimes with small red dots near the bases. The fruit is a capsule about 3 centimeters long containing shiny seeds.