In New York, Dunn re-encountered Softness, who volunteered to be his manager.
He also befriended actress Phoebe Dorin in an off-Broadway show, Two by Saroyan, in which both had small parts in the early 1960s.
They began singing together casually after their nighttime performances, sitting on the wall of the fountain opposite the Plaza Hotel, and drew a following.
Eventually, on the advice of fellow actor Roddy McDowall, the pair started a nightclub act of songs mixed with conversational patter, titled "Michael Dunn and Phoebe".
The act received favorable reviews in Time magazine and The New York Times and ultimately led directly to the pair being cast on The Wild Wild West television series, a Western spy spoof with elements of historical fiction and science fiction, which debuted in 1965.

Dunn was probably best known for his recurring role on that series as Dr. Miguelito Loveless, a mad scientist who devised passionately perverse schemes and gadgetry to ensnare Secret Service agents James West and Artemus Gordon (Robert Conrad and Ross Martin). (
Note: Miguelito is the Spanish diminutive of Michael, equivalent to Mike or Mikey.)
Dorin played Dr. Loveless's devoted assistant, Antoinette.
In each episode in which they appeared together, the villainous couple tenderly sang a Victorian duet or two, heedless of the mayhem they had created around themselves.
According to Dorin, Dunn saved her from drowning during filming of the episode The Night of the Murderous Spring, plunging underwater to tear her free, when her costume became entangled in machinery used to sink a boat on the set.
Dunn appeared as Dr Loveless 10 times on "The Wild Wild West" (four times apiece in the first two seasons and one time apiece in the remaining two seasons).

In the pilot episode of the Mel Brooks and Buck Henry television spy spoof Get Smart, Dunn showed his skill with comic farce as the well-heeled gangster Mr. Big, leader of international crime organization K.A.O.S. (September 18, 1965).
Dunn featured as Alexander, a courageous court jester, in the Star Trek episode "Plato's Stepchildren" (November 22, 1968). (
Alexander caps his solo about the Greek god Pan with a guttural, onomatopoeic quotation—"brekekekex, koax, koax"—from the Aristophanes comedy, The Frogs, written in about 405 B.C.)  He also appeared in an episode of Bonanza, "It's A Small World" (January 4, 1970), portraying a recently widowed circus performer trying to start a new life, and as a killer clown in the Voyage to the Bottom of the Sea episode "The Wax Men" (5 March 1967).

In 1963, he received the New York critics' Circle Award for best supporting actor and was nominated for a 1964 Tony Award, for his performance as Cousin Lymon in Edward Albee's stage adaptation of The Ballad of the Sad Café, by Carson McCullers.
Dunn received an Oscar nomination and the Laurel Award as the best supporting actor for his role as the cynical Karl Glocken in Ship of Fools (Columbia Pictures, 1965, directed by Stanley Kramer).

In 1969, The New York Times drama critic Clive Barnes praised Dunn's portrayal of Antaeus in the tragedy The Inner Journey by British novelist and playwright James Hanley, performed at the Lincoln Center: "Michael Dunn as the dwarf is so good that the play may be worth seeing merely for him.
Controlled, with his heart turned inward, his mind a pattern of pain, Mr. Dunn's Antaeus deserves all the praise it can be given."

Between those career highlights, he accepted roles in many pulp horror movies, as well as a role in the 1968 film No Way to Treat a Lady, starring Rod Steiger and George Segal.
However, at the time of his death, he was in London playing Birgito in The Abdication (Warner Brothers, 1974, directed by Anthony Harvey), starring Peter Finch and Liv Ullmann.
Author Günter Grass had already asked him to play in a film adaptation of his novel, The Tin Drum, a role that ultimately went to the young David Bennent after Dunn's death.
In New York, Dunn re-encountered Softness, who volunteered to be his manager. He also befriended actress Phoebe Dorin in an off-Broadway show, Two by Saroyan, in which both had small parts in the early 1960s. They began singing together casually after their nighttime performances, sitting on the wall of the fountain opposite the Plaza Hotel, and drew a following. Eventually, on the advice of fellow actor Roddy McDowall, the pair started a nightclub act of songs mixed with conversational patter, titled "Michael Dunn and Phoebe". The act received favorable reviews in Time magazine and The New York Times and ultimately led directly to the pair being cast on The Wild Wild West television series, a Western spy spoof with elements of historical fiction and science fiction, which debuted in 1965.
Dunn was probably best known for his recurring role on that series as Dr. Miguelito Loveless, a mad scientist who devised passionately perverse schemes and gadgetry to ensnare Secret Service agents James West and Artemus Gordon (Robert Conrad and Ross Martin). (Note: Miguelito is the Spanish diminutive of Michael, equivalent to Mike or Mikey.) Dorin played Dr. Loveless's devoted assistant, Antoinette. In each episode in which they appeared together, the villainous couple tenderly sang a Victorian duet or two, heedless of the mayhem they had created around themselves. According to Dorin, Dunn saved her from drowning during filming of the episode The Night of the Murderous Spring, plunging underwater to tear her free, when her costume became entangled in machinery used to sink a boat on the set. Dunn appeared as Dr Loveless 10 times on "The Wild Wild West" (four times apiece in the first two seasons and one time apiece in the remaining two seasons). 
In the pilot episode of the Mel Brooks and Buck Henry television spy spoof Get Smart, Dunn showed his skill with comic farce as the well-heeled gangster Mr. Big, leader of international crime organization K.A.O.S. (September 18, 1965). Dunn featured as Alexander, a courageous court jester, in the Star Trek episode "Plato's Stepchildren" (November 22, 1968). (Alexander caps his solo about the Greek god Pan with a guttural, onomatopoeic quotation—"brekekekex, koax, koax"—from the Aristophanes comedy, The Frogs, written in about 405 B.C.)  He also appeared in an episode of Bonanza, "It's A Small World" (January 4, 1970), portraying a recently widowed circus performer trying to start a new life, and as a killer clown in the Voyage to the Bottom of the Sea episode "The Wax Men" (5 March 1967).
In 1963, he received the New York critics' Circle Award for best supporting actor and was nominated for a 1964 Tony Award, for his performance as Cousin Lymon in Edward Albee's stage adaptation of The Ballad of the Sad Café, by Carson McCullers. Dunn received an Oscar nomination and the Laurel Award as the best supporting actor for his role as the cynical Karl Glocken in Ship of Fools (Columbia Pictures, 1965, directed by Stanley Kramer).
In 1969, The New York Times drama critic Clive Barnes praised Dunn's portrayal of Antaeus in the tragedy The Inner Journey by British novelist and playwright James Hanley, performed at the Lincoln Center: "Michael Dunn as the dwarf is so good that the play may be worth seeing merely for him. Controlled, with his heart turned inward, his mind a pattern of pain, Mr. Dunn's Antaeus deserves all the praise it can be given."
Between those career highlights, he accepted roles in many pulp horror movies, as well as a role in the 1968 film No Way to Treat a Lady, starring Rod Steiger and George Segal. However, at the time of his death, he was in London playing Birgito in The Abdication (Warner Brothers, 1974, directed by Anthony Harvey), starring Peter Finch and Liv Ullmann. Author Günter Grass had already asked him to play in a film adaptation of his novel, The Tin Drum, a role that ultimately went to the young David Bennent after Dunn's death.
Michael Dunn (actor)