Image of the Fendahl is the third serial of the 15th season of the British science fiction television series Doctor Who, which was first broadcast in four weekly parts on BBC1 from 29 October to 19 November 1977.
The serial was Chris Boucher's third and final script for the series and is set in an English priory, where the cultist Max Stael (Scott Fredericks) prepares the scientist Thea Ransome (Wanda Ventham) to be possessed and transformed by an ancient gestalt alien called a Fendahl.
In a priory near the village of Fetchborough, four scientists, Adam Colby, Max Stael, Thea Ransome and Dr. Fendelman, are doing tests on a human skull they found in Kenya, apparently twelve million years old.
He and his followers capture Colby, kill Fendelman, who was actually influenced through his genetics by the Fendahl to bring this about, and set up the Sonic Time scanner to power the skull and Thea's final transformation.
The Doctor frees Colby and helps Stael shoot himself after killing one of the new Fendahleen, in turn finding out that they are fatally allergic to salt, leaving the Fendahl core two short of the twelve it needs to be complete and form a gestalt.
The Doctor rigs the scanner to implode upon itself and grabs the now dormant skull, leaving with the others only just before the priory is destroyed, along with the Fendahl core and the remaining Fendahleen.
[3] Boucher never wrote for the series again, immediately after this becoming script editor on Blake's 7 for four years and as the BBC didn't want anyone working on two shows at the same time.
Producer Graham Williams had worked with director George Spenton-Foster previously on Z-Cars and chose him to direct this serial due to his experience with night filming.
Scott Fredericks had played Boaz in 1972's Day of the Daleks and was later cast by Spenton-Foster in the Blake's 7 episode "Weapon" alongside Graham Simpson who also appears in this story.
Paul Cornell, Martin Day, and Keith Topping wrote in The Discontinuity Guide (1995) that Image of the Fendahl was "one of the best stabs at outright horror in Doctor Who's history".
"[7] In The Television Companion (1998), David J. Howe and Stephen James Walker felt that the scripts were "a little vague when it comes to certain details about the Fendahleen" and the Fendahl was "something of a disappointment", but they praised the supporting characters, in particular Daphne Heard's performance, who "plays the role to perfection and is largely responsible for conveying the sense of high tension and anticipation in the latter episodes".
He praised Baker's performance, saying he was "fully engaged with the drama, providing a pleasing balance of gravitas and flippancy" but noted that Leela was "toned down".
He acknowledged that it is "often cited as the last gasp of the horror sub-genre prevalent in earlier seasons" but added that "punches are pulled" and regarded it as "more like a tale of the supernatural" with "atmospheric night filming and an unusually eerie soundscape."
[9] DVD Talk's John Sinnott gave Image of the Fendahl three and a half out of five stars, praising the atmosphere but noting that the slow start and "rather convoluted story" held it back from being a classic.