David Hemmings plays Thomas, a photographer in London who likes to bark to his models, thinking he is above them. One afternoon he photographs 2 lovers in Maryon Park, but the woman (Vanessa Redgrave) chases him and tells him that she wants the negative. This makes Thomas curious so he gives her another roll. After he blowups the pictures, he thinks he has photographed a murder. The enlarged, distorted pictures show a gunman and the body. Thomas goes to the park that night to find that the body is still there, but when he returns to his apartment, the pictures are gone.
There is an interesting scene when Thomas spots the mysterious woman (Redgrave) on his way to find his friend that night. He tries to find her by entering into a concert of The Yardbirds. The guitarist goes mad because the sound system goes wrong, and he breaks his guitar and throws the neck to the audience who goes wild. Thomas wins and runs out, chased by a mob. Outside the building, when he is no longer chased, he throws away the guitar's neck. This time the relic is seen as a trash - none wants it.