The film is loosely based on the Modesty Blaise comic strip created and written by Peter O'Donnell. O'Donnell wrote the scenario for the movie, but the screenplay went through multiple rewrites and the end result differs significantly from the original. Changes range from the relatively trivial, such as hair colour, to ones that horrified the comic strip's fanbase:the coldly competent Modesty is depicted as a bubbly (though still strangely comptetent) airhead, and Platonic Life-Partners Modesty and Willie fall in love and deciding to get married.
The storyline is as follows: Modesty, a secret agent whose hair color, hair style, and mod clothing change at a snap of her fingers, is being used by the British government as a decoy in an effort to thwart a diamond heist. She is being set up by the feds but is wise to the plot and calls in sidekick Willie and a few other friends to outsmart them. Meanwhile, at his island hideaway, Gabriel, the diamond thief, has his own plans for Blaise and Garvin.
O'Donnell wrote a novel based on his version of the screenplay, which (unlike the film) was successful and led to many sequels.
Since the film's release, there have been two additional films produced adapting the comic strip: a 1982 Pilot for a never-produced Americanized series that aired as a TV movie featuring Ann Turkel in the lead role, and in 2004, My Name is Modesty was a low-budgeted production starring Alexandra Staden as a young Modesty prior to her meeting Willie Garvin.
This film provides examples of:
- Absolute Cleavage: Modesty impersonates a prostitute in Amsterdam's red-light district by pulling down the zipper of her cat suit to her navel. She is not wearing anything underneath.
- Action Girl: Even though Modesty has been chickified compared to the comic strips, she doesn't shy away from fights or demanding physical activity.
- Adaptation Dye-Job: Modesty is blonde and Willie isn't, the reverse of their hair colours in the comic strip. She does change it to her original colour in a couple of scenes, perhaps as a form of lampshading, and Willie likewise is seen in his normal blonde style early in the film as well before going dark-haired for the rest.
- Arab Oil Sheikh: Abu Tahir, who adopted Modesty as his "son".
- Camp: The high type.
- The Cavalry: The charge at the end done by Abu Tahir and his troops.
- A Glass of Chianti: Gabriel lounges with a huge glass of blue wine while dispensing his evil orders. To underscore his decadence, a live goldfish is swimming in the glass.
- Ambiguously Gay: Gabriel has effeminate mannerisms and likes to surround himself with young, bare-chested men. He doesn't show any overt sexual interest in anyone, though, and could possibly be Camp Straight or even asexual. His obvious admiration for Modesty seems to be more of the professional than sexual kind.
- Bad Boss: Mrs. Fothergill, who submits her minions to dangerous tests of their physical abilities (when one of them doesn't return alive from a diving test, she seems mostly happy to be rid of an inept underling) and takes obvious sadistic glee in forcing them to do strenuous physical exercise.
- Changing Clothes Is a Free Action: Played straight and exaggerated for comedy. Modesty doesn't just change her entire outfit, as well as her hair style and hair colour, from scene to scene (whether she'd realistically have the possibility or not) but quite often the change takes place between cuts within a scene. In at least one case there isn't even a cut; her hair just instantly blinks from blonde to dark while we're watching.
- In Name Only: Zigzagged. Peter O'Donnell famously stated that the film retained only one line from his original screenplay, and his novelization (which kicked off the Modesty Blaise book series) bears little resemblance to the movie beyond characters and certain setpieces.
- Knife Fight: In Amsterdam, both Modesty and Willie end up fighting an opponent with knives at the same time.
- Leaning on the Fourth Wall: This exchange:Gabriel: I am the villain of the piece. I have to condemn you.
Modesty Blaise: But I am the heroine. Don't I get away?
- At one point images of the real-life Modesty Blaise comic strip are shown.
- Protagonist Title
- Psycho for Hire: Mrs. Fothergill, who has sadistic tendencies and seems to enjoy killing.
- She likes to submit her (Gabriel's actually) minions to physical exercise of a potentially deadly kind.
- She visibly enjoys strangling the mime who has betrayed their plans and throwing him off a cliff.
- She seems a bit too eager to remind Gabriel that he has promised her to kill Modesty and/or Willie.
- Relationship Upgrade: Modesty and Willie decide to get married once the adventure is over. And the action comes to a halt while they do a song and dance number about it - once in the middle of the movie, and once again towards the end.
- Scenery Porn: For fans of architecture, the opening credits that play out over images of classic '60s building lines is as good as Playboy.
- Sissy Villain: Gabriel has rather effeminate mannerisms and tastes. He can also be rather squeamish about the people he "have to" kill.
- Vapour Wear:
- Many scenes imply that Modesty, in contrast to int he comic strip, never wears any underwear. The effect is somehat ruined by the actress's bra and panties sometimes showing through her clothes.
- When Modesty is strip-searched by the bad guys, she takes off her dress and is then implied to be naked (but not shown to be, due to SceneryCensors). Mrs. Fothergill takes a look at her nether regions and says
- That's nice, but woolen knickers down to your knees is better for your health.
- Volleying Insults: During the period of "truce" between Modesty and Gabriel:Gabriel: Suffragette!
Modesty Blaise: Psychopath!