Truth be told, there's not much actual strangling going on here, especially in the first hour, which sees Captain Harry Lewis (Rolfe) investigating the disappearances of, literally, thousands of people in and around the titular Indian city. His boss, Colonel Henderson (Cruickshank) only takes him seriously when trade caravans start to vanish, but doesn't bother letting Lewis look into things, instead appointing Captain Connaught-Smith, a chum who went to the same school (the part is played by Allan Cuthbertson, who was Colonel Hall in the "Gourmet Night" episode of Fawlty Towers). Lewis continues to dig, comes to the attention of the Kali cult leader (Pastell), and is captured, though is released, through what can only be a called a deus ex mongoosea. But with the cult preparing to take down the caravan to end all caravans, about to leave Bombay under the eye of Connaught-Smith, they realize that letting go the Westerner who was investigating them, may not have been such a wise idea.
I like how the poster screams, "This is true! This is real! This actually happened!" as if one of those statements isn't actually enough. Well... It's based on true events, though the dying out of the Thuggees perhaps had as much to do with the arrival of railway, providing cheap, safe transport through the rural areas in which they operated, as the efforts of the British army. Still, who'd go see a movie about Indian trains? That aside, this is mostly pedestrian stuff, that feels more like a history book on the topic than an exciting action-adventure yarn, despite some similarities to The Temple of Doom. Rolfe might as well be made out of cardboard, and there's little sense of danger. The only exception is the attack on the caravan, as the Thuggees materialize out of the jungle around Connaught-Smith and his men; it's a nicely-creepy moment, in what is otherwise a fairly dull and forgettable effort, with little of the style we've come to expect from Hammer.