The movie was made to capitalize in the popularity of Tom Selleck's Magnum character from the TV series Magnum, P.I. (1980). Movie poster tag-lines boasted, "The Magnum Man Hits the Big Screen with a Vengeance".

This wartime espionage movie co-stars Jane Seymour who had been a Bond Girl in the James Bond espionage film Live and Let Die (1973).

Tom Selleck's suave debonair gentleman thief character Nick Lassiter was written in the spirit of Cary Grant's John Robie from To Catch a Thief (1955).

The movie's opening title card states: "London June 1939".

Classic vehicles seen in this movie included a vintage motor-cycle and a black Mercedes Coupe.

Brian Coburn was dubbed by David de Keyser.

Debut theatrical feature film directed by Roger Young.

Lassiter is the only movie where Jane Seymour is seen nude. She is seen from the rear and side.

One of the movie's scenes is lifted right out of The Sting (1973).

Star Billing: Tom Selleck (1st), Jane Seymour (2nd), Lauren Hutton, Bob Hoskins (4th), Joe Regalbuto (5th), Ed Lauter (6th) and Warren Clarke (7th).

Lauren Hutton's role as sexy German spy Kari Von Fursten in this 1984 film was a "Mata Hari' type character. A new version of Mata Hari (1985) would be made and released the following year in 1985.

The value of the uncut Nazi diamonds was US $10 million.

One of two 1984 movies starring actor Tom Selleck first released in that year. The other picture was Michael Crichton's Runaway (1984). Both films had one word titles with three syllables.

Actor Tom Selleck has starred in such espionage-related movies as Killers (2010_, Lassiter (1984),The Gypsy Warriors (1978), and The Washington Affair (1977).

The film's "Lassiter" title refers to the last name of the movie's lead central character of Nick Lassiter portrayed by Tom Selleck.

The name of the underground night-club was "The Crypt".

Intelligence agencies featured in the film were Scotland Yard and the Federal Bureau of Investigation (FBI).

Ronald Neame was originally attached to direct according to an article published in the 6th January 1983 edition of show-business trade paper 'Daily Variety'.

The movie was originally going to be set in New York city in the USA according to an article published in the 27th August 1983 edition of 'Screen International' but was changed to London in England as 1939 was more indicative of the approaching wartime Europe of the 1940s. It should be noted on this point that the United States of America did not enter WWII until much later after the Second World War had started.

Lauren Hutton plays a sexy deadly blonde murdering Mata Hari seductress called Kari Von Fursten who kills her male victims during sex with a stiletto hair-pin in a movie made and released just eight years before Sharon Stone made this type of story element famous in Basic Instinct (1992).