Louis Mahoney appeared in two Classic Who serials, one with the Third Doctor and the other with the Fourth. In the first, Frontier in Space (1973), he had a one episode part as a 26th century newscaster reporting on a Draconian-Galaxy battlecruiser potentially attacking an Earth-based cargo ship. For his 1975 role in Planet of Evil, He played Ponti, a crewmember aboard a Morestran probe ship sent to Zeta Minor in the year 37166. He is assigned the job of bringing in the Doctor and Sarah Jane, but alas, he meets an untimely demise. Jumping ahead to 2007, Mahoney plays the older version of Billy Shipton in Blink who meets with Sally Sparrow in his hospital bed. Though his elder self only appears for a few minutes on screen, it is through him that fans learn just how the Tenth Doctor was able to communicate through the DVD Easter eggs that would eventually rescue the TARDIS.