Shannon and the Show Boat

Sir William Hedges, concerned about the fire hazard of a Mississippi showboat, engages Aubrey Mason's firm to provide a fire guard while the vessel, owned by the dubious Seamus Camber, begins operations on the Thames. Mason assigns an operator named Cannon to watch over the ship, where he soon encounters various characters, including Duke Delaney, who appears to be involved with the showboat's furnishings and is suspicious of Camber. Tensions rise as Camber, encouraged by Delaney, bets on reaching twenty knots, risking the old boat's integrity. Cannon uncovers a woman named Constance Maston hiding on board, who turns out to be an undercover Interpol agent tracking Delaney for using the showboat as a front for stealing valuable artworks. As the situation escalates, it becomes clear that Delaney has been manipulating events to make it appear as though Camber is at fault, but ultimately, his plans are thwarted when Maston reveals his true identity and intentions, ensuring that Delaney faces justice instead.