In April 1956, 14-year-old Kirk was cast as
Joe Hardy for
The Mickey Mouse Club serial
The Hardy Boys, alongside
Tim Considine as
Frank Hardy. The first of the serials,
The Mystery of the Applegate Treasure, was filmed in June and early July 1956, and aired in October at the start of the show's second season. In the following year, the second serial
The Mystery of Ghost Farm aired in 1957. The show and Kirk's performance were extremely well received and led to a long association between the actor and the Disney studio. A year prior to being cast in
The Hardy Boys, Kirk first auditioned for another serial
Spin and Marty, but was unsuccessful. The open audition took the form of a baseball game. In August 1956, Disney hired him and the former Mouseketeer Judy Harriet to attend both the
Republican and
Democratic presidential nominating conventions, for newsreel specials that later appeared on the show. Kirk also hosted short travelogues for the serial segment of the show's second season, sometimes with
Annette Funicello. He did the voice-over narration for "The Eagle Hunters" and dubbing work for the Danish-made film
Vesterhavsdrenge, shown on the
Mickey Mouse Club as the serial "Boys of the Western Sea". Around this time, it was announced that Kirk would appear as Young
Davy Crockett, but this did not happen. '' (1957) Kirk's career received its biggest break yet when, in January 1957, Disney cast him as Travis Coates in
Old Yeller (1957), an adventure story about a boy and his heroic dog. Kirk had the lead role in the film, a success at the box-office, and he became Disney's first choice whenever they needed someone to play an all-American teenager.
Kevin Corcoran played his younger brother and the two of them were often cast as brothers. '' In July 1958, Kirk was cast in
The Shaggy Dog (1959), a comedy about a boy inventor, who under the influence of a magic ring, is repeatedly transformed into an
Old English Sheepdog. This teamed him with Corcoran and Considine, and two other Disney stars with whom he regularly worked,
Fred MacMurray and
Annette Funicello. According to
Diabolique, "Much of the credit went to MacMurray; a lot of the credit should have gone to Kirk, whose easy-going boy next door charm made him the ideal American teen." (At the same time,
Film Daily called Kirk one of its five "male juveniles" of the year, the others being
Tim Considine,
Ricky Nelson,
Eddie Hodges, and
James MacArthur.) With his Disney contract completed, Kirk went to
Universal Pictures, where he played the male lead in the English dub of a Soviet animated feature,
The Snow Queen, opposite
Sandra Dee.
Shaggy Dog turned out to be a hit, gaining significantly larger rentals than
Old Yeller, and Disney soon contacted Kirk, offering him another long-term contract and a role as middle son Ernst Robinson in another adventure film,
Swiss Family Robinson (1960), starring
John Mills,
Janet Munro, and once again
Dorothy McGuire as his onscreen mother and Corcoran. It remained Kirk's favorite movie. When he returned from filming in the
West Indies, the studio signed him to two more movies. Kirk followed up with a secondary role in a fantasy comedy starring Fred MacMurray,
The Absent-Minded Professor (1961), another huge hit. Disney sent Kirk to England for
The Horsemasters (1961), a youth-oriented horse riding film, which was made for U.S. television, but screened theatrically in some markets. He appeared once more with Munro and Funicello. That same year, Kirk played the support role of Grumio in the
fairy tale fantasy
Babes in Toyland, supporting Funicello,
Ray Bolger,
Ed Wynn and
Tommy Sands. Kirk later described this film as "sort of a clunker ... but it has a few cute moments, it's an oddity", and enjoyed working with Ed Wynn. It was a box-office disappointment; so too was
Moon Pilot (1962), a satirical comedy where Kirk played the younger brother of
Tom Tryon. Kirk also had trouble with Jane Wyman, saying: "She was very mean to me. She went out of her way to be shitty ... but she was a total bitch and I think she was
homophobic." Kirk maintained better relationships with his onscreen brothers Kevin Corcoran and Tim Considine, who called Kirk "a monster talent". Kirk starred with Funicello in another overseas-shot story which screened in the United States on TV, but was released in some countries theatrically:
Escapade in Florence (1962). Newspaper columns occasionally linked Kirk and Funicello's names romantically, though in fact, they were never anything more than friendly coworkers. Instead, he did a sequel to
Absent Minded Professor,
Son of Flubber (1963), his last film with MacMurray. In 1963, Kirk reprised his role as Travis Coates in Disney's
Savage Sam (1963), a sequel to
Old Yeller, which reunited him with Corcoran and co-starred
Brian Keith; it was not as well received as
Old Yeller. Disney then cast Kirk as student inventor Merlin Jones in
The Misadventures of Merlin Jones (1964), again opposite Funicello. The film was directed by
Robert Stevenson, who was frequently assigned Disney comedies. It became an unexpected box-office sensation, earning $4 million in rentals in North America, and Disney invited Funicello and him back to make a sequel, ''The Monkey's Uncle
(1965). The Monkey's Uncle
came out in July 1965 and was almost as successful as Merlin Jones''. == Television ==