Juggernaut is really a very low budget film that holds interest as it was one of several British films made by Boris Karloff after he made his name in Hollywood for making horror films for Universal Pictures.
Karloff plays Dr Sartorius somewhere in north Africa whose funding for medical experiments has been cut. Distraught he succumbs to the dastardly plans of Yvonne Clifford (Mona Goya) a greedy, philandering wife of a rich old man. She wants Sartorius to poison her husband so she can inherit his fortune and he gets money for his research. Her plans become unstuck when she finds out that her stepson will administer his father's estate.
Goya is wildly over the top in her performance, Karloff is rather laid back even though he is playing a sinister role.
There is actually a rather short film but still packs a plot and some poor acting.