This tale of espionage and high risk romance begins at a Paris railroad depot as Karen Schöntag, the Austrian alias of the Russian Carla Vanirska (Constance Bennett) attempts to board an overbooked train for Vienna.
Well, as good fortune, perhaps, would have it, Captain Rudolph "Rudy" Ritter (Gilbert Roland), en route to Vienna himself, to his newly-promoted position as Captain of an Austrian intelligence agency, enables Karen/Carla to accompany him because he instantly succumbs to her charms and graces.
Now, the balance of the film transpires in Vienna, as Rudy and Major Lieber (Edward Ellis) lead the search for the capture of the dangerous enemy agent "K-14," who cleverly delivers coded messages to comrades of a Russian insurgency movement to attempt to overthrow the government in Austria. (Well, keep in mind that this is a 1933 release, and before the period of WWII German occupation.)
So, you may pretty well guess the identity of K-14 from the list of IMDb cast credits, but what a clever operator K-14 turns out to be, writing those secret coded messages in invisible ink, folding them into the pages of books, entering the secret rendezvous locations, tapping the steps of a staircase by the shoe, and delivering the set of books to a fellow agent, who hides beneath the staircase to slide a secret panel to receive them.
Fans of the Classics may find many elements of manners, glamor and suspense, with the lovely leading lady carrying the film, all reasons to tune into vintage films. "After Tonight," well staged with excellent cinematography, does, however, seem to have a screen-story of conflicting allegiance for fans to wonder whom or what we're supposed to be rooting for here.
According to IMDb, "The film lost $100,000 at the box office, which made the studio (RKO Radio Pictures) consider firing Miss Bennett," making her the scapegoat in an awkwardly scripted outing, which seems to loose its direction and climax in a rather somewhat implausible finale.
But Constance Bennett does carry the film well, as its prime attraction, and she handles the material to cause even the more irate critics to care about her character--especially after bodies begin to fall victim to conflicts between the caucuses.
So, in addition to Miss Bennett, Mr. Roland and Mr. Ellis, you may also recognize Sam Godfrey as Franz, Lucien Prival as Lieutenant Erlich, Mischa Auer as Agent Lehan, and Virginia Weidler in the role of Olga, Carla's Niece.
And it would also be nice to score with half-points here and there.
Edit 03/24/16 -- "...first sentence saying it begins in a Paris railroad station. It actually begins in Luxembourg, which is a different country and 250 miles away." -- (Thanks for correction, IMDb Member blakedw.)