Johann Radek (Franchot Tone) is a sly, kooky character dining across the cafe. Radek passes a note to Mr. Kirby, offering to murder the wealthy aunt.
Because his glasses are left at the scene, Heurtin is first implicated in the murder. Heurtin helps the police identify Radek, but Radek is so sneaky and clever that he is able to taunt the police. Charles Laughton is brilliant as the lead inspector working to bait and catch Radek.
Phantom Lady, Eiffel Tower is where we first see Franchot's face (a bit more lined with wrinkles and wisdom) taking on the characteristics that he would display in his television work. His hair and clothes are somewhat disheveled and his eyes are full of mischief.
You can watch The Man on the Eiffel Tower on Youtube or at the Moving Image Archive. There is also a DVD available on Amazon.