It was produced by Alan Ladd, Jr. and Stanley Mann, from a screenplay by William Spier based on the traditional Scottish poem The Ballad of Tam Lin.

[citation needed] The Monthly Film Bulletin wrote: The beginning is not promising: tricksy angles, glossy decor and photography, smart-set drug junketings that echo the last days of Swinging London.

What develops is perhaps even less palatable as the young lovers meet on the Scottish moors in the glowing soft focus terms of a TV commercial, romping about with the progress of their love recorded in a series of freeze frames.

From there on, however, with the dialogue beginning to take on an edge of brilliance, Roddy McDowall gets a much firmer grip on the film, building a broodingly enigmatic sense of menace out of stray allusions and apparitions that hover without ever really being explained or over-exploited ...

When it finally does come, the climax tends to be a little too excited for its own good; but it has some excellent notions ... and an ending not unworthy of The Hounds of Zaroff [1932] with lan McShane being pursued through a misty forest by a pack of hell-hounds conjured by his own imagination.