Eyewitness is a 1970 British thriller film directed by John Hough and starring Mark Lester, Susan George and Lionel Jeffries. Its plot follows a young English boy who, while staying with his grandfather and adult sister in Malta, witnesses a political assassination, and is subsequently pursued by the killers—however, due to his habitual lying, those around him are hesitant to believe his claims. It is an adaptation of the novel by Mark Hebden, the pen name for John Harris, and bears similarity to Cornell Woolrich's novelette "The Boy Cried Murder", originally adapted for film as The Window.

Mark Lester is an English former child actor who starred in a number of British and European films in the 1960s and 1970s. In 1968 he played the title role in the film Oliver!, a musical version of the stage production by Lionel Bart based Charles Dickens' novel Oliver Twist He is one of three last surviving actors of Said film along with Shani Wallis and Kenneth Crannham. Lester also made several appearances in a number of British television series. In 1977, after appearing in the all-star international action adventure film The Prince and the Pauper, he retired from acting. In the 1980s, he trained as an osteopath specialising in sport injuries.