Mistaken identity and underhanded dealings set the stage for this adventure story based on Anthony Hope's classic novel. Rudolph Rassendyll (Stewart Granger) is a British tourist visiting the nation of Ruritania in the Balkans. A number of people comment upon Rassendyll's remarkable resemblance to Prince Rudolph, who in a matter of days is to be crowned the nation's new king, and the prince's staff even arranges a meeting between the two men. But Rudolph's devious brother believes it is he who should be the king, and he arranges for Prince Rudolph to be poisoned the night before his coronation. Desperate, Rudolph's minders beg Rassendyll to participate in the ceremony in Rudolph's place so that the usurper cannot take the throne. Rassendyll agrees, and the ceremony goes off without a hitch, but when the brother's men discover this subterfuge, they imprison the real Prince as they threaten to reveal the secret of the new "king." Rassendyll's dilemma is compounded when he finds himself falling in love with Princess Flavia (Deborah Kerr), Rudolph's intended. This was the fourth screen adaptation of The Prisoner of Zenda; a fifth, which focused on the tale's comic possibilities, starred Peter Sellers and was released in 1979.
~ Mark Deming, All Movie Guide