Season 1:
Indira Stefanianna Christopherson (circa Juliet Prowse)
Elizabeth Montgomery (circa Connie Stevens)
Charro (circa Ruth Buzzi, Rita Moreno)
Bobby Sherman (circa Florence Henderson, Paul Williams)
Tennessee Ernie Ford (circa Charles Aznavour)
Rip Taylor (circa Lena Horne, Peter Ustinov)
Burl Ives (circa Bruce Forsythe, Sandy Duncan)
Carly Simon (circa Sandy Duncan, Candice Bergen)
Shirley Jones (circa Candice Bergen, Avery Schreiber)
Nipsey Russell (circa Avery Schreiber, Ben Vereen)
James Caan (circa Ben Vereen)
Michelle Phillips of The Mamas & The Papas (circa Twiggy, Kaye Ballard)
Billy Joel (circa Mummenschanz)
Season 2:
Groucho Marx (circa Don Knotts, Zero Mostel)
Mel Brooks (circa Zero Mostel, Milton Berle)
Tim Conway (circa Rich Little, Nancy Walker)
Lee Remick (circa Edgar Bergen)
Buddy Hackett (circa Madeline Kahn)
Jack Gilford (circa George Burns)
Red Skelton (circa Bernadette Peters, Rudolf Nureyev)
The Electric Light Orchestra (circa Elton John)
Christopher Lee (circa Julie Andrews)
Carole King (circa Peter Sellers)
Karen Valentine & Biff & Sully (circa Bob Hope)
Paul Lynde (circa Teresa Brewer)
ABBA (circa Cloris Leachman)
Season 3:
Harry Chapin (circa Leo Sayer, Roy Clark)
Seals & Croft (circa Jean Stapleton, Alice Cooper)
Johnny Rivers (circa Marisa Berenson, Raquel Welch)
Flip Wilson (circa Raquel Welch, James Coco)
Jose Feliciano (circa Helen Reddy)
Billy Davis & Marylin McCoo (circa Danny Kaye, Spike Milligan)
Leon Redbone (circa Elke Sommer)
John Ritter (circa Lynn Redgrave)
Season 4:
Thelma Houston (circa John Denver)
The Spinners (circa Dyan Cannon, Victor Borge)
Ed Asner (circa Linda Lavin, Dudley Moore)
Dan Fogelberg (circa Kenny Rogers, Lola Falana)
Audrey Landers (circa Jonathan Winters, Christopher Reeve)
Adam West (circa Lynda Carter)
Sammy Davis Jr. (circa Carol Channing, Andy Williams)
Robin Williams (circa Doug Henning, Alan Arkin)
Cher (circa Diana Ross)
Season 5:
Gunther Rebel Williams (circa Gene Kelly)
Elliott Gould (circa Loretta Swit, Joan Baez)
Art Garfunkel (circa Senor Wences, Jean-Pierre Rampal)
Donna Summer (circa Paul Simon, Melissa Manchester)
Charles Nelson Reilly (circa Mac Davis, Carol Burnett)
David Odgen Stiers (circa Gladys Knight, Marty Feldman)
Richard Pryor (circa Chris Langham)
France Joli (circa Johnny Cash, Buddy Rich)
Rex Harrison (circa Roger Moore)