Its first UK broadcast was on 11 December 1968 by Thames Television, who commissioned this series of the show for the ITV network.
Three thousand top-secret and super-powerful FF70 rifles are stolen and come up on the black market for auction.
Filmed between October 1967 and February 1968, "Have Guns — Will Haggle" started as the pilot episode of the sixth series of The Avengers.
In its original conception, entitled "Invitation to a Killing", it ran for 90 minutes and introduced the character of Tara King.
However, when original producer John Bryce was replaced by Albert Fennell and Brian Clemens, they decided to begin the series with "The Forget-Me-Knot" which explicitly introduced the character, so "Have Guns — Will Haggle" was moved to midway through the run.