Tonight, SERIES PREMIERE, 10:01 p.m. ET (History)
Why You Should Watch: Looking to duplicate the formidable success of “Vikings,” this 10-part scripted historical action drama goes inside the Knights Templar, the medieval military order entrusted with protecting the most precious relics in Christianity. “You’d Know What to Do,” the series premiere, opens in the 13th century, after the fall of the city of Acre, the Templar’s last stronghold in the Holy Land. Landry (Tom Cullen), a knight, fears that the Order has lost its way. Padraic Delaney and Simon Merrells also star.