Das Indische Grabmal (aka The Indian Tomb) (1921)

A British architect (Olaf Fonss) is commissioned by an Indian maharajah (Conrad Veidt) to create a large monument, only to learn that it is meant for the maharajah's unfaithful lover (Erna Morena), who will be buried alive as punishment. Based on the novel by Thea  Von Harbou (who adapted her novel for the screen with her then husband Fritz Lang) and directed by Joe May. This epic is over four hours long but it was meant to be seen in two parts and if seen in one sitting, it can be occasionally tedious especially in the second part which tends to languish more than it should. Edited down to to a tight three hours and you might have an epic adventure on a grand scale. The sets are spectacular and the art direction by Erich Kettelhut and Karl Vollbrecht are impressive. Fritz Lang would remake the film in 1959 in color and although it too is long and meant to be seen in two parts, I think it's a much better movie. With Mia May (the director's wife), Lya De Putti, Bernhard Goetzke and Paul Richter.