Therefore, its known narrative elements are not a part of the Doctor Who universe as we, on this Wiki, choose to define it. It may have been the basis for a similar story in another medium, however — and that story may indeed be valid.
The Horror of Fang Rock was a story concept in John Leekley's series bible for Amblin Entertainment's proposed 1990s Doctor Who television show. It was based on the Fourth Doctor story Horror of Fang Rock.
Following streaks of light through the galaxy, the Doctor and Borusa arrive at a lighthouse on Land's End, England, in 1906. A clipper ship runs around in the strange sea fog; the Doctor helps rescue the survivors but is suspected by the crew after their captain is mysteriously murdered. Realising that an alien mothership has crashed at the lighthouse and the alien used the lighthouse keeper's body to send the streaks of light for a rescue party, the Doctor proves his innocence by destroying the alien and its ship.