Watch Legion of Brothers (2017) HD Full Movie Free on SolarMovie. Watch Legion of Brothers (2017) online free. Immediately after the 9/11 attacks, fewer than 100 US Troops were sent on a secret mission to overth...Immediately after the 9/11 attacks, fewer than 100 US Troops were sent on a secret mission to overthrow the Taliban. What happens next is equal parts war-origin story and cautionary tale, illuminating the impact of 15 years of constant combat.