Title: Lost in Space (2018 TV series)
Content: AnnaMaria Demara as Tam Roughneck, a mechanic and friend to Don West ; Selma Blair as Jessica Harris, June's wealthy younger sister ; Bill Mumy as Zachary Smith, the real Dr. Smith whose identity June steals. As a child, Mumy portrayed Will Robinson in the original Lost in Space series from 1965 to 1968. ; June Lockhart as June (denoted by subtitles), a radio communications officer on Alpha Centauri (credited as "the Voice of Alpha Control"). June Lockhart portrayed Maureen Robinson in the original Lost in Space series from 1965 to 1968. She also made a cameo as the principal of Will Robinson's school in the 1998 film. ; Angela Cartwright as Sheila Harris, June's mother. As a child, Cartwright portrayed Penny Robinson in the original Lost in Space series from 1965 to 1968. She also made a cameo, as a reporter, in the 1998 film. ; Rob LaBelle as Mr. Jackson, the school teacher aboard the Resolute ; Karen LeBlanc as the chancellor of the Alpha Centauri base 
Title: Lost in Space (film)
Content: William Hurt as Professor John Robinson ; Mimi Rogers as Professor Maureen Robinson ; Heather Graham as Dr. Judy Robinson ; Lacey Chabert as Penny Robinson ; Jack Johnson as Will Robinson ; Jared Harris as Older Will Robinson ; Matt LeBlanc as Major Don West ; Gary Oldman as Dr. Zachary Smith / Spider Smith ; Dick Tufeld as the voice of Robot ; Lennie James as Jeb Walker ; Mark Goddard as General ; June Lockhart as Principal ; Marta Kristen as Reporter #1 ; Angela Cartwright as Reporter #2 ; Edward Fox as Businessman ; Gary A. Hecker as voice of Blarp 
Title: Lost in Space
Content: Cameo, not part of the main cast ; Poses as "Dr. Smith" Notes:
Title: Lost in Space
Content:  Control's doctor, is revealed to be a saboteur working on behalf of an unnamed nation. After disposing of a guard who catches him aboard the spacecraft, Smith reprograms the Jupiter 2s B-9 environmental control robot (Bob May, voiced by Dick Tufeld) to destroy critical systems on the spaceship eight hours after launch. Smith becomes trapped aboard at launch, however, and his extra weight throws the Jupiter 2 off course, causing it to encounter asteroids. This, plus the robot's rampage, causes the ship to prematurely engage its hyperdrive, and the expedition becomes hopelessly lost in the infinite depths of outer space. Smith's selfish actions and laziness frequently endanger the expedition, but his role assumes less sinister overtones in later parts of the series.
Title: Jonathan Harris
Content:  on Harris' character, Dr. Smith. While the series was still solidly placed in the middle of the ratings pack, the writers appeared to run out of fresh ideas, and the show was unexpectedly cancelled in 1968 after 83 episodes, despite protests from its fans. Harris was succeeded in the role of Dr. Smith by Gary Oldman in the 1998 film version, who played the role as a more genuinely menacing and less likeable character than Harris's on television. For the 2018 reboot of Lost in Space as a Netflix original series, Parker Posey was cast as Dr. Zachary Smith, a female psychopath using a stolen identity to assume the role of the ship's psychologist.
Title: Space Academy
Content:  The program starred veteran actor Jonathan Harris, best known as Dr. Zachary Smith of Lost in Space; co-starring were Pamelyn Ferdin, Ric Carrott, Maggie Cooper, Brian Tochi, Ty Henderson, and Eric Greene. The program featured a pint-sized robot called "Peepo", a radio-controlled machine voiced by Erika Scheimer talking through a pitch-shifter with regenerative delay. Guest stars included Lawrence "Larry" Dobkin; Dena Dietrich ("Mother Nature" in the Chiffon margarine TV commercials of the 1960s and 70s); George DiCenzo; Dallas McKennon; and Howard Morris.
Title: Lost in Space (film)
Content:  pilot, who is replaced by hotshot fighter pilot Major Don West, to his chagrin. The family's physician Dr. Zachary Smith, a Sedition spy, sabotages the ship's on-board robot before launch, but is betrayed by his cohorts and left unconscious as the ship launches and the family enters cryosleep. The robot activates and begins to destroy the navigation and guidance systems, en route to destroying the family. Smith awakens the Robinsons and West, who manage to subdue the robot, but the ship is falling uncontrollably into the Sun. Forced to use the experimental hyperdrive with an unplotted course, the ship is transported through hyperspace 
Title: Lost in Space (2018 TV series)
Content:  petty criminal who assumes the identity of her sister, Jessica, to take her place on the Resolute. She subsequently steals and alters the credentials of Dr. Zachary Smith during the first attack to become "Dr. Zoe Smith" and take his seat on an evacuating Jupiter ship. The theft of the doctor's identity is a reference to the corresponding character of Dr. Smith in the original television series (also, her character, June Harris, is named for June Lockhart, who played Maureen Robinson, and Jonathan Harris, who played Smith on the original series). ; Brian Steele as the Robot (seasons 2–3; recurring season 1), an alien 
Title: Lost in Space
Content:  Despite being credited as a "Special Guest Star" in every episode, Smith became the pivotal character of the series. The show's writers expected Smith to be a temporary villain who would only appear in the early episodes. Harris, on the other hand, hoped to stay longer on the show, but he found his character to be boring, and feared it would also quickly bore viewers. Harris "began rewriting his lines and redefining his character", by playing Smith in an attention-getting, flamboyant style, and ad-libbing his scenes with colorful, pompous dialogue. By the end of the first season, the character of Smith is established as a self-serving coward. These character traits are magnified in subsequent seasons. His haughty bearing, and ever-present alliterative repartee, were staples of the character.
Title: Lost in Space
Content:  In the 1972–1973 television season, ABC produced The ABC Saturday Superstar Movie, a weekly collection of 60-minute animated movies, pilots and specials from various production companies, such as Hanna-Barbera, Filmation, and Rankin-Bass. Hanna-Barbera Productions contributed animated work based on such television series as Gidget, Yogi Bear, Tabitha, Oliver Twist, Nanny and the Professor, The Banana Splits, and Lost in Space. The Lost in Space episode aired on September 8, 1973. Dr. Smith (voiced by Jonathan Harris) was the only character from the original program to appear in the special, along with the Robot (who was named Robon and employed in flight control rather than a support activity). The spacecraft was launched vertically by rocket, and Smith was a passenger rather than a saboteur. The pilot for the animated Lost in Space series was not picked up as a series, and only this episode was produced. This cartoon was included in the Blu-ray release of the entire original television series on September 15, 2015.

Question: who played doctor smith in lost in space?
Answer: Jonathan Harris.