Watch In the Tall Grass (2019) HD Full Movie Free on SolarMovie. Watch In the Tall Grass (2019) online free. After hearing a young boy's cry for help, a sister and brother venture into a vast field of tall gra...After hearing a young boy's cry for help, a sister and brother venture into a vast field of tall grass in Oklahoma but soon discover there may be no way out...and that something evil lurks within.