It is an adaptation of the Philo Vance novel of the same name. Archibald Coe is an obnoxious jerk who is basically asking to be murdered. His niece Hilda Lake (Astor) resents Coe for controlling her and for refusing to let her have her inheritance, which is in a trust. His brother Brisbane Coe just generally despises him. His secretary Raymond Wrede is in love with Hilda and hates Coe for refusing to saction the union. Another of Hilda's suitors, Sir Thomas MacDonald, hates Coe because he thinks Coe killed his dog—Coe's and Thomas's dogs were scheduled to compete against each other in a dog show, hence the title of the movie. Liang, Coe's Chinese cook, had helped Coe amass a priceless collection of Chinese antiquities and is outraged that Coe is going to sell the collection for a profit. Eduardo Grassi, who has contracted to buy the collection on behalf of the Italian government, is enraged when Coe renegs on the contract after finding out that Grassi is dating Coe's ex-lover, Doris.
Basically, everybody hates Archibald Coe and no one is sorry when he's dead. The cops call it suicide, as Coe was found in a locked room with a gun in his hand. But private detective Philo Vance isn't convinced; he was at the dog show and knows how much Coe wanted to win. Vance insists the cops look more closely, and sure enough it turns out Coe was murdered. It's left to Vance to sort through the tangled mass of suspects.
Last of five films where William Powell played Philo Vance. The next year he played a different detective, Nick Charles in The Thin Man.
- Asshole Victim: No one liked Archibald.
- Colliding Criminal Conspiracies: Brisbane sneaks in to the house, finds Archibald in his bedroom, and shoots him in the head, never realizing that Archibald was dead already. This gets Brisbane killed moments later by the real murderer.
- Conversation Cut:
- Someone asks who the neighbor is, and she's identified as "Doris Delafield." Cut to Doris in the next scene, saying "Yes, I'm Doris Delafield."
- Vance and Markham have to lay a trap for the killer. Vance looks at his watch and says "Come on Markham, we've got to get there before—". Cut to Vance and Markham at the trap, with Vance saying "—4:45."
- The Dying Walk: The flashback shows Coe, who doesn't realize he's been stabbed and is bleeding to death, walk unsteadily upstairs to his bedroom. He then goes on to open the windows, and is sitting in a chair taking his shoes off when he dies.
- Elective Broken Language: Liang speaks to Vance in Asian Speekee Engrish, but Vance calls him out as a faker. Liang then switches to his regular voice and admits he went to Columbia.
- I'm a Doctor, Not a Placeholder: Over 30 years before Dr. McCoy, the doctor in this movie is called to the scene of the crime, questioned by bystanders, and replies "I'm a doctor, not a magician". A few minutes later, he pronounces a man to have committed suicide and is reminded he's supposed to look at the body, to which he replies "I'm a doctor, not a detective".
- Inspector Lestrade: Detective Heath (Eugene Palette) is an absolute idiot, getting the solution wrong constantly. He's at least self-aware enough to let Vance due the real work.
- Match Cut: From Heath pulling out his handcuffs to a detective measuring the round end of Grassi's shoes.
- Model Planning: Vance uses a model of the Coe residence and the apartment building next door to demonstrate how the murder went down.
- Murder by Mistake: Brisbane gets killed because Wrede mistook him for Archibald.
- Necro Cam: Shows the murder as Vance explained how it happened. An unusual example in that the face of the murderer isn't shown and we don't find out who it is until the next scene.
- Never One Murder: Having found out that Archibald Coe was murdered, Vance and the cops are starting to zero in on Brisbane as the suspect, until Vance opens a closet in the lobby and Brisbane's corpse tumbles out.
- Never Suicide: The cops simply assume that Coe shot himself because he was found in a locked room. Once they find a head wound and a stab wound in his back, they're forced to re-evaluate.
- Running Gag: The doctor continually being bothered by the police calling him to the scene.
- Time-Delayed Death: Turns out that Coe got whacked on the head and then stabbed downstairs. He woke up not realizing that he's been stabbed and is bleeding to death internally. He made it upstairs and to his bedroom before he died in his chair.
- Worst News Judgment Ever: "ARCHER COE COMMITS SUICIDE" probably didn't need to be above the fold.