Some of these pictures and descriptions may give away plot details that you might not want to know before watching the film.
This was a quirky British spy television series that aired from 1961-1969, starring John Steed (Patrick Macnee) an eccentrically suave British Intelligence agent who drives an old sports car with a television in the dashboard and can defeat his foes with little effort. His partner, Emma Peel (Diana Rigg), appears in seasons 4-6, including this episode about an exclusive club for men called "The Hellfire Club" modeled after an 18th century club with the same name with the goal of toppling the government and taking over. The new club members are licentious noblemen who want to drink, have orgies, and watch fights, believing that "...women are vessels of pleasure." (Basically, exactly like any college fraternity.) The club is run by John Cleverly Cartney (Peter Wyngarde) a rich playboy who observes another man's use of practical jokes to humiliate public figures and copies the idea, using them for murder instead of humiliation. Ultimately he plans to kill a bunch of important politicians. This sics the Avengers on Cartney. They infiltrate a big Hellfire Club event called "The Night of All Sins" where Cartney makes Peel change her outfit to become "The Queen of Sin" in a skimpy outfit holding a snake.
On stage, Carney announces to the crowd that it's the "witching hour" and introduces Emma Peel as "...a symbol of all that is evil, as the epitome and purveyor of this Night of Sins - the Queen of Sin." She walks onto the stage and Carney takes off a black robe that covers her and the camera slowly raises up from her boots to her face. Her outfit, designed by Rigg herself, consists of tall black pointed high-heeled boots, a black corset so short that it doesn't even cover her underwear, black elbow gloves, a spiked dog collar, and a shackle on one wrist attached to a chain attached to her back. She is also holding a snake, which is a great accessory, but probably unnecessary given the rest of the smoke show. (I wonder if the snake was Riggs' idea when she designed the outfit of if someone else added it.) The "Queen of Sin" outfit was too much for the American TV censors in 1964, so they banned the episode.
Carney then tells the crowd that "She is yours to do with what you will." Immediately the crowd rushes the stage, hoists her onto their shoulders, and carries her away to another room, still clutching the snake in one hand. After Peel is abducted, we see a long shot of the snake alone in front of a fireplace slowly crawling up to a sculpture of the head of Pan, the lustful Greek god. After that I expected to see that they had dragged Peel to an orgy, or something as outrageous, but instead, we see her sitting and looking bored in a room with people watching two men fight. Then we see another long shot of the snake crawling on top of the Pan sculpture.
That's all for the snake, but there are lots more great shots of Peel in dominatrix mode, fighting a man with her sharp boots and the chain on her wrist, and ultimately using a whip to defeat Carney and send him down a trap door.
The well-behaved snake is a Ball Python, a popular pet species from Africa that is known to do exactly what this one does - wrap around an arm and hang on tight when they're carried around. The snake's Latin name is Python regius and it is also called the Royal Python, which stems from the legend that ancient African royalty wore the snakes as live jewelry as Emma does.