Curzon employs the brash and confident Logan to save his ailing business. However Logan's confidence is not matched by his ability and his desperate measures lead to a life threatening situation.
With his marriage failing, a man hires a german assassin to murder his wife, who he suspects is having an affair. Things seem to go to plan at first, until the assassin decides not to kill the woman, but rather kidnap her, while still collecting his fee for the job. The husband wants proof of the muder (a body) before he pays. Things go wrong for both men when proof is not forthcoming.
A victim's boyfriend sneaks into a blackmailer's flat to sort him out, but another man's already there, and both don't realise the crook has been murdered before they got there. The police soon arrive, tipped off in advance.
Supt. Meredith is determined to bring a team of wealthy blackmailers to book. As he piles on the psychological pressure, the criminals begin to look for ways to betray each other and escape with a fortune in diamonds.
An international criminal arrives in London, and a detective is anxious to pin something on him for some unprovable murders of former lovers. The villain starts to suspect servants and henchmen of being a police spy known as "Number Six".
Burglars rob a townhouse and most of them are caught at the scene, but valuable jewels seem to have vanished. An estate agent realises they are still on site, and tries to purchase the building before anyone finds them.
Jewel thieves graduate to murder when their elderly hostage dies.
A German immigrant girl seduces a young P.C. and talks him into an elaborate scheme.
A Private Eye's boss is murdered.
Blackmail is the dividend a stockbroker (Albert Lieven) earns for keeping his ex-client's money.