"Mr. Blandings Build His Dream House" (1948), in which Cary Grant wanted to move from the city to the country, solidified their success and led to several vehicles written, produced and directed in tandem. Their joint efforts ranged from slight comedies to well-crafted dramas. "The Reformer and the Redhead" (1949) was a minor romantic comedy in which June Allyson was a zoo-keeper's daughter courted by Dick Powell. The pair made the unnecessary 1951 remake "Strictly Dishonorable", based on a 1931 Preston Sturges' play. "Callaway Went Thataway" (1951), starring Fred MacMurray, was a spoof of Hopalong Cassidy while "Above and Beyond" (1952), a biopic of the pilot who dropped the atomic bomb on Hiroshima showed their dramatic flair. In 1953, Panama and Frank earned their second Oscar nomination for the Danny Kaye vehicle "Knock on Wood" and the following year, they wrote what is perhaps their best known feature, the Crosby and Fred Astaire classic "White Christmas", with its memorable Irving Berlin title song. The duo followed with the superlative Danny Kaye swashbuckler spoof, "The Court Jester" (1955), which critic Leonard Maltin has deemed "one of the best comedies ever made". A rousing costume musical that offered Kaye one of his best screen roles, the film utilized every cliche but played them for laughs. Adding to the enjoyment was the excellent supporting cast that included Glynis Johns, Basil Rathbone, John Carradine, Angela Lansbury and Mildred Natwick.
Unfortunately, Panama and Frank had difficulty finding a successful follow-up. "That Certain Feeling" (1956) was a lame comedy that miscast Bob Hope as a cartoonist. With the changing times, Panama and Frank headed to Broadway to adapt the Al Capp hillbilly comic strip "Li'l Abner" as a musical. They produced the show as well as wrote the book and lyrics to Johnny Mercer's music. A modest success on stage in the mid-50s, Panama produced and Frank directed the 1959 film version, which while well-acted, flopped. By this time, Panama and Frank had begun spitting duties, although they continued to write together. Panama alone directed the psychological drama "The Trap" (1958) and the final Hope-Crosby-Lamour match up, "The Road to Hong Kong" (1962). Panama and Frank continued to work together until 1966's "Not With My Wife You Don't", which Panama directed. Frank then elected to move to Great Britain and set up his own company and the 30-plus year partnership faded. (Frank would go on to thrive with romantic comedies like 1972's "A Touch of Class" and 1976's "The Duchess and the Dirtwater Fox"). Panama continued to work within the changing structures of Hollywood. He directed the modest Bob Hope vehicle "How to Commit Marriage" and the failed horror spoof "The Maltese Bippy" (both 1969). Teaming with Albert E. Lewin, Panama went on to co-script and direct his last feature (to date) "I Will...I Will...For Now" (1975), a look at marriage and marriage counseling with Elliot Gould and Diane Keaton.
On the small screen, the new team of Panama and Lewin co-wrote (with Panama helming) the TV-movie "Coffee, Tea or Me" (CBS, 1973), about a flight attendant with two husbands and they contributed scripts to the Teresa Graves series "Get Christie Love" (ABC, 1974-75). Panama's last TV project was the Australian update of the comic strip "Barbaby and Me" (1976). In 1980, he and Lewin co-wrote the novel "The Glass Bed".