This movie was remade in 1956 with Doris day and James Stewart. The movies are similar but not the same. The Lawrences (Edna Best, Leslie Banks and daughter Betty, Nova Pilbeam) travel to Switzerland for a skiing event. There mother participates in a shooting contest, and loses as one of the finalists to Ramon Levine (Frank Vosper), In addition to being a marksman he is part of an terrorist group headed by Abbott (Peter Lorre). That evening at dinner their new friend, Louis Bernard (Pierre Fresnay) is shot. Before he dies he tells them to get a note intended for the British consul. They find the note which tells of an assassination plot. However before they can tell anyone, their daughter is kidnapped. However they understand that the bad guys are headed to London as the assassination is to take place at the Royal Albert Music Hall. Clive (Hugh Wakefield) and father, Bob look for the girl . The track one of the kidnappers to a temple of a sun worshipping cult. Father is captured but Clive gets away and helps to expose the group. Mrs. Lawrence goes to the concert indicated on the note. Her scream effects the aim of Levine and he wounds rather than kills the intended victim. But he gets away, sneaking out in the chaos, but they are able to track his vehicle to the sun temple, which sets up a final gun battle. Many police die, as do all the criminals, including Betty's nurse and Abbott love (Cicely Oates). Father found his daughter and helped her escape, but Levine was after her and catches her on the roof. They are exposed to the police below. It is a tricky shot and the police officer marksman hesitates. Mrs Lawrence takes te gun and makes the shot. Abbott is hiding in a closet and his watch gives him away, so he takes his own life.
This is a very good early Hitchcock movie. It also takes on the spy theme which becomes a Hitchcock trade mark.