Large sums of counterfeit currency have begun to flood the world’s markets. Drake shadows the chief suspect, General Gunther von Klaus (Christopher Rhodes), and finds that his attractive daughter, Mitzi (Moira Redmond), provides him with some cover. But not for long ….

My interest was piqued right from the pre-credits teaser. It begins with POV shots of someone searching for something – after they find a suitcase stuffed with banknotes the door opens and a typically icy-looking Roger Delgado guns the unfortunate searcher down before he can utter a word. That’s a decent opening, especially since the promise of more Delgado to come is always an appealing one.

Drake gets several chances to exercise his charm on Mitzi, although theirs is a very chaste relationship. Other series might have gone further and featured more manipulation, but things are quite innocent here. As for von Klaus, Drake’s charm hits a brick wall as the General remains impervious to his polite social entreaties.

This means that von Klaus is a rather colourless character for the first half of the story, speaking only infrequently and then quite abruptly. But things begin to evolve once the action moves to the Sea Hotel, located on the shores of Lake Geneva.

This is where Delgado (playing hotel owner Von Golling) reappears and it quickly becomes clear that all Von Golling’s staff are equally as villainous as he is (Walter Gotell as the receptionist, for example). But there’s something of a dichotomy here – on the one hand the hotel caters for the rich and seems to have a good reputation, but on the other we see that Von Golling isn’t adverse to killing off his guests if they discover too much. Surely that will affect bookings ….

Drake and von Klaus take a cable car to the top of the mountain in a key scene which swiftly reverses the dynamic between the pair. Initially von Klaus has the upper hand, taunting Drake with the possibility that he could fall or be pushed from a great height before Drake drops his cowed act and establishes control.

This scene confirms that although von Klaus is the frontman of the money scam he isn’t in charge. Drake senses that he’s been coerced somewhere along the line and offers him a way out (although he’s never given a chance to repent as Von Golling murders him as soon as he returns to the hotel). I’d like to have had a little more detail about von Klaus’ motivations, but as ever with the 25 minute format, the clock is ticking.

The episode climaxes with a tense standoff as Drake and Mitzi are hunted through the deserted hotel by Von Golling and his henchman. I know it’s been established that many of the guests have set off on a boat trip, but it slightly stretches credibility that absolutely everyone has gone.

Never mind, the police turn up in the nick of time and all’s well, except that Drake has to (off-screen) break the news of her father’s death to Mitzi. As for the mystery of the money, the clue’s in the episode title (a secret stash of Nazi banknotes which I’m surprised haven’t turned into a sodden mess after being underwater for twenty five years).

This is another strong Jack Whittingham script that clips along at a fair rate. As I’ve said, it would have been nice to have dug into the character of von Klaus a little more, but that’s about the only niggle I have.

The cast is a strong one and in addition to those already mentioned, there’s a nice comic turn from Hermione Baddeley as a garrulous American tourist. With a brief bit of location filming at Portmeirion, this has to rate as one of the strongest from the first series.