Rasputin... The Mad Monk
1966

Mad, he was bloody furious, I can tell you. Hammer's over-wrought entry into the almost-straight historical drama-cum-horror genre is actually a bit of a masterpiece, despite being saddled with crap production values and a galloping lack of actual historical accuracy.
It's also Christopher Lee's finest Hammer hour, as he finally gets the chance to cut loose and be what he is, a larger-than-life ham.
Lee's performance as the original hairy krishna is actually what makes the film so good (which is a rarity). From his overpowering entrance into the bar at the beginning (he looks huge) to his eventual over-the-top murder, he overshadows everyone else (literally, at some points). It's the part he was born to play, and he knows it. Whether he's out-drinking an entire pub, seducing and then abandoning Barbara Shelley, or plotting the murder of the Tsarina, he's never less than brilliant. And this is from someone who finds him dull and overrated in practially every other horror film he's graced.
Unfortunately, Lee's powerhouse performance is pretty much the whole film. Produced back-to-back with Dracula - Prince Of Darkness, Rasputin shares identical sets, the same cast and even the same wardrobe (by the look of it), which tends to detract from the proceedings slightly. When the Tsarina eventually does get thrown from the castle walls, you half expect him to land on Dracula as he frantically scrabbles to stay afloat on his ice floe. They're that similar.
And as Russia's greatest love machine hypno-murders, acid-chucks and hand-lops his way through the cast, you tend to find yourself on the side of the far more interesting and less cardboard-like Lee. All the other characters are just there to be mutilated, driven insane or chucked off the battlements.
The final scenes are fantastic, though, as everyone finally decides they had enough of the by-now bonkers (never mind just mad) Monk, who, in best Jason Vorhees-style, refuses to lie down when poisoned etc.
Rasputin - The Mad Monk may be mild compared with the excesses of the other stuff Hammer was chucking out at the time (there's no throat cutting, staking, zombie beheadings, or hideous snakebites to contend with), but where it scores is in its (shaky) basis in historical fact, Lee's powerhouse performance, and that 70s silver-clad funksters Boney M wrote a song about it. You don't get better than that.

Rasputin: The Mad Monk (1966)
Director: Don Sharp Writer(s): Anthony Hinds (as John Elder)
Cast: Christopher Lee - Grigori Rasputin, Barbara Shelley - Sonia, Richard Pasco - Dr. Zargo, Francis Matthews - Ivan, Suzan Farmer - Vanessa, Dinsdale Landen - Peter, Renée Asherson - Tsarina, Derek Francis - Innkeeper, Joss Ackland - The Bishop, Robert Duncan - Tsarvitch, Alan Tilvern - Patron, John Welsh - The Abbot, John Bailey - The Physician, Mary Barclay - Superior Lady, Michael Cadman - Michael, Helen Christie - First Tart, Lucy Fleming - Wide Eyes, Michael Godfrey - Doctor, Fiona Hartford - Tania, Prudence Hyman - Chatty Woman, Bryan Marshall - Vasily, Bridget McConnell - Gossip, Jay McGrath - Dancer, Robert McLennan - Dancer, Bartlett Mullins - Waggoner, Veronica Nicholson - Young Girl, Mary Quinn - Innkeepers Wife, Michael Ripper, Celia Ryder - Fat Lady, Cyril Shaps - Foxy Face, Leslie White - Cheeky Man, Brian Wilde - Vassily`s Father, Maggie Wright - Second Tart, Jeremy Young - Court Messenger