week, with Martin opening the door to reveal an unannounced celebrity guest. Most of the time, Martin did not know who the guest would be, to keep his reactions more spontaneous, according to Hale's book Backstage at the Dean Martin Show. A regular gag during one season was the "Mystery Voice Contest", wherein Martin invited viewers to write in to guess who was singing a particular song. Invariably, it was the famous Frank Sinatra hit "Strangers in the Night." Finally on one episode, Sinatra appeared to announce that he was the mystery singer. Martin handed over the prize, a trip to Los Angeles, where they already lived. The finale was typically a production number featuring Martin and the guest stars. Occasionally it would be a musical sketch with Martin appearing as "Dino Vino", a disc jockey who played old records. A vintage record would then be heard, with Martin and his guests mouthing the words and pantomiming outrageously. During the show's eighth season, the finale was a selection of songs from a popular MGM film musical. Clips from the selected film would be shown, with Martin and guests singing a medley from the films. Among those saluted were Easter Parade, Words and Music, Till the Clouds Roll By and the 1951 film version of Show Boat. When the show was canceled in 1974, a series of Dean Martin Celebrity Roast specials were produced in Las Vegas at the MGM Grand Hotel. This tradition was started during the final season of the variety show and continued until 1984. Regulars and recurring guests In later seasons, many regular performers were added, such as Dom DeLuise and Nipsey Russell in sketches set in a barber shop; Kay Medford and Lou Jacobi in sketches set in a diner, and Medford also pretending to be the mother of Martin's pianist, Ken Lane. Leonard Barr, Guy Marks, Tom Bosley, Marian Mercer, Charles Nelson Reilly, and Rodney Dangerfield were also featured on multiple occasions, while bandleader Les Brown was a regular. During the inaugural 1965–1966 season, the Krofft Puppets were seen in eight episodes. Sid and Marty Krofft recall that they were fired because of an incident involving Liberace, for whom they had previously worked, and who was a great fan of their puppets. Sid Krofft states: "And he [Liberace] asked his fan club to write Dean Martin a letter and tell Dean Martin that there isn't