Puppet on a Chain is a 1970 British thriller film directed by Geoffrey Reeve and starring Sven-Bertil Taube, Barbara Parkins and Alexander Knox.

[3] After three hippie drug-dealers are murdered by "the assassin" in a house in Los Angeles, the U.S. government sends special agent Paul Sherman to track down the Dutch source of heroin that is causing the drug war.

On arriving at Amsterdam Schiphol Airport, Sherman witnesses an agent, Jimmy Duclos, who was there to meet him, shot dead by the assassin.

Sherman is originally from the Netherlands, but it is clear that Amsterdam's chief of police, Colonel De Graaf, is unhappy with having the Americans interfere in Dutch affairs.

However, Sherman's direct contact, Inspector Van Gelder, is more cooperative, since his niece, Trudi, suffers from severe brain damage caused by a heroin overdose eight years earlier.

[6] The famous boat chase sequence was performed by Wim Wagenaar[7] and directed by Don Sharp who was specifically hired to do it over a four-week period.

[8] Sharp: The chappie who directed originally [Geoffrey Reeve, who died in 2010] has gone on to produce some nice movies, and before this he had a good career in shooting commercials.

But he didn’t have a story sense then, as a director, and he and his camera operator, each set-up, you know, a sequence that looked like part of a television commercial and wasn’t there for the drama of it, or just to let the audience know what was happening.