If you've ever looked at lists of Academy Award winners, you may recall that the first winner of the Best Actor Oscar is listed as Emil Jannings, usually for The Way of All Flesh. Unfortunately, The Way of All Flesh is presumed lost with the exception of one scene. However, in that first edition of the awards, the acting awards were technically supposed to be for an actor's body of work over that "season", the "seasons" running from August through July much like later TV seasons. (Note also that up until 1934, the lists give two years, eg. 1927-1928, for the period in question.) Jannings was also the lead in another movie that helped him win that Oscar, and that movie survives: The Last Command.
Jannings plays Sergius Alexander, who at the start of the movie is a Russian émigré in Hollywood taking work as an extra. Director Leo Andreyev (William Powell in an early role, unmistakable since he already has that moustache) is also an émigré, and is looking for someone to play the part of a Russian general. He sees Sergius, and realizes that Sergius would be perfect for the role, in part because Sergius was a general before the Revolution. Indeed, we're about to get that back story....
In one of Hollywood's most original plot devices, we get Yet Another Flashback, this time to the era of the Russian Revolution. Sergius isn't just a general; he's a Grand Duke and a cousin of tsar Nicholas II who of course would be executed a few months after the action of the flashback, so Sergius wouldn't exactly be liked by the communists. But he's not near Saint Petersburg with the tsar and his family; instead, he's out in the field commanding troops. An acting troupe is also traveling around Russia to entertain the troops, but a couple of Sergius' men inform him that two of the troupe at least are revolutionaries: the aforementioned Leo, and Leo's companion Natasha (Evelyn Brent).
With a revolution on, Sergius should probably have the two killed, but he makes the serious mistake of letting them live, in part to torment them and in part because Natasha is pretty. It's a big mistake, because they're not going to return the favor of leniency. Well, at least Leo isn't. Natasha finds herself falling in love with Sergius, so she keeps looking for reasons to keep Sergius alive even as the Bolsheviks close in. Now, of course we know that Sergius survives since he has to wind up in Hollywood (as does Leo), but how do the stories of these three characters play out?
Reading up on the reviews of The Last Command, it seems that it has acclaim from those in the know as a masterpiece. I personally wouldn't rate it quite so high, although it's definitely a darn good movie and one that's worth a watch. The story may be a bit unrealistic, but that doesn't take away from the fine acting.