Though the story told in Robin and Marian is unfamiliar to most audiences, it is actually quite faithful to several of the ancient Robin Hood legends. During the Crusades, Robin (Sean Connery) is still loyal to King Richard the Lionheart (Richard Harris), but even he has trouble adjusting to the monarch's ever-increasing paranoia and lunacy.
After Richard's death, Robin returns to England, his first visit to his home turf in 20 years. He looks up his beloved Maid Marian (Audrey Hepburn, last seen in 1967's Wait Until Dark), who is now a middle-aged nun.
No sooner do Robin and Marian renew their relationship than the aging Merry Men demand Robin's services in thwarting their old foe, the Sheriff of Nottingham (Robert Shaw). Marian is aghast that the long-standing feud between Robin and the sheriff threatens to expand into wholesale bloodshed.
The two venerable enemies agree to one last mano a mano battle -- only to watch helplessly as the all-out war they'd tried to avoid commences anyway. Both the tragic climax and Robin's last, defiant arrow shot are drawn directly from authentic Robin Hood ballads of the 14th and 15th centuries.