Number Seventeen

Detective Barton arrives at the unlocked house at Number 17 and an unknown candle-wielding figure roams the scene. A dead body is found, and the stranger claims innocence when confronted. Barton, who introduces himself as Fordyce, probes the intruder about the contents of his pockets, while a shadowy hand reaches for a doorknob.

Ms. Ackroyd is seen crawling on the roof in shadows. After she falls through the roof, she is revived and reveals that her father is on the roof and that they are next door in Number 15. She hints at danger from the surrounding thieves.

The bell tolls half past midnight, and the dead body has disappeared, creating confusion among the occupants. The vanish fuels suspicion and sets the stage for the visitors. Tension rises as the night unfolds.

Three people arrive: Brant, Nora, and Henry Doyle. Ben produces a pistol and accidentally shoots Barton, Fordyce, in the arm. The tense confrontation escalates as the group takes stock of the situation.

Brant orders Doyle to search Barton, Ben, and Rose Ackroyd. A telegram is revealed to Brant, and Sheldrake appears to retrieve a diamond necklace hidden in the upper part of a toilet. The thieves grow bolder as the case tightens around them.

Ben causes a commotion and is locked away with Sheldrake in the toilet. The trap deepens as the two thieves confront each other while the others search for Rose and Barton. The ruse continues as Ben plans to outlast his captors.

The supposed corpse turns out to be alive and pretends to be Sheldrake to fool the thieves. In a twist, he is revealed as Rose's missing father, a police officer, adding an unexpected ally to the mix. This revelation complicates the thieves' plan.

Officer Ackroyd locks away the thieves and frees his daughter Rose and Barton. He confronts Sheldrake in a fistfight, gaining the upper hand before being overwhelmed. The balance of power shifts as the law closes in.

Nora reveals she can speak by uttering 'I'm coming back' and returns to the basement to buy time for the others to escape. Rose and Barton are freed again, though Rose faints and recovers. The group then frees Ben and Ackroyd.

The thieves arrive at the railyard and board a departing freight train bound for the German States. Their plan centers on seizing the diamond and slipping away as the train departs. Tension builds as the escape route tightens.

Ben staggers onto crates of wine on the moving train and drinks as chaos erupts. The thieves dispatch the conductor, shoot the fireman, and seize the driver as he faints. The chase escalates as Barton and the others realize the danger.

Barton commandeers a bus to chase the fleeing train, while Doyle is revealed to be a detective posing as a thief. The pursuit intensifies as the necklace becomes the central prize. Tensions rise as loyalties blur.

A high-speed train chase ends with Doyle escaping and handcuffing Nora. The balance of advantage shifts once more as the true identities come into play. The thieves' plan begins to unravel.

The train accelerates toward the dock while the criminals struggle to slow it. The ferry arrives and the train crashes into the other train on the ferry, pushing both into the sea. Passengers are rescued from the water as rescue efforts continue.

Doyle reveals he is actually Detective Barton, while Fordyce admits to being the real Barton and explains the police strategy. The plan exposes Sheldrake and frees the innocent. All thieves except Nora are apprehended, and Ben reveals that he still has the diamond necklace.