Olaf Pooley Olaf Pooley was an English actor who portrayed the Cleric in the episode . His second wife , Gabrielle Beaumont ( his first wife being the actress Irlin Hall with whom he has a daughter , the actress Kirstie Pooley , born in 1954 ) directed that episode . Beaumont had previously directed Pooley in a 1978 edition of pre - school program " Rainbow " , in a 1978 episode of " Shadows " , in the 1984 television movie " Gone Are the Dayes " ( co - starring Bibi Besch ) , in a 1989 episode of " The Paradise Club " , in a 1990 episode of " TECX " , in a 1992 episode of " L . A . Law " , in a 1996 episode of " Dr . Quinn , Medicine Woman " ( starring Joe Lando ) , and the 1996 television movie " Beastmaster : The Eye of Braxus " ( co - starring Patrick Kilpatrick , Tony Todd , and David Warner ) . Pooley and Beaumont married in 1982 but later separated . Having played Professor Stahlman and his parallel Earth counterpart Director Stahlman in the " Doctor Who " serial in 1970 , Pooley is one of the few actors to have appeared in both the " Star Trek " and the " Doctor Who " franchises . Pooley has appeared in a number of British productions since the late 1940s , making his film debut in the 1948 mystery " Penny and the Pownall Case " . His subsequent credits include 1950 ' s " Highly Dangerous " , 1952 ' s " This Woman ' s Angle " ( which also featured a young Joan Collins ) , and 1956 ' s " The Iron Petticoat " . He also had roles in the BBC series " Gravelhanger " ( 1954 ) and " Leave It to Todhunter " ( 1958 ) . His first American production was 1956 ' s " Anastasia " , although this was filmed in Europe and his appearance went uncredited . In the 1960s , he made appearances on such popular British shows as " The Four Just Men " , " Sherlock Holmes " , " The Troubleshooters " , " Dixon of Dock Green " , and " Paul Temple " . His film credits during this time included 1966 ' s " Naked Evil " ( starring Lawrence Tierney ) and 1969 ' s " The Assassination Bureau " ( with Clive Revill ) . Pooley wrote and appeared in the 1970 horror film " Crucible of Horror " ( aka " The Corpse " ) . He also wrote , directed , and co - starred in the 1971 comedy " The Johnstown Monster " . In addition , he continued making appearances on British series , including " Doomwatch " , " Jason King " , " Special Branch " , " The Zoo Gang " ( starring Brian Keith ) , and the first episode of " The Sandbaggers " . And , in 1974 , he co - starred with Patrick Stewart , as well as Tony Jay and John Rhys - Davies , in the acclaimed mini - series " Fall of Eagles " . He went on to co - write the 1980 horror mystery " The Godsend " , which was directed by his wife , the aforementioned Gabrielle Beaumont . His other writing credits include the 1982 television film " Falcon ' s Gold " and being an uncredited writer on the 1985 sci - fi film " Lifeforce " , which starred the aforementioned Patrick Stewart . Pooley ' s remaining acting credits include the 1985 television movie " Wallenberg : A Hero ' s Story " , with Alice Krige , a role in the pilot episode of " MacGyver " and roles in " Charlie Muffin " , " An Evening with Rosanne Seaborn " , and " Fellini ' s Donut " . Pooley died on 14 July 2015 at the age of 101 due to congestive heart failure . At the time of his death , he was the oldest living " Star Trek " or " Doctor Who " actor . Following his death , Norman Lloyd inherited the distinction of being the oldest known living " Star Trek " performer .