Billy Crystal is an actor, comedian writer/producer, and film director. He gained
prominence in the 1970s for playing Jodie Dallas on the ABC sitcom Soap and
became a popular film star during the late 1980s and 1990s, appearing in the 
box office comedy successes When Harry Met Sally (1989), and City Slickers
(1991). He has hosted the Academy Awards eight times.

Barbara Feldon is a character actress of both stage and television who
is primarily known for the role of Agent 99 on the popular 1960s sitcom 
Get Smart on NBC and later CBS. Following her first work as a model,
Feldon’s break came in the form of a popular and much parodied TV
commercial (shown below) for "Top Brass," a hair pomade for men.

Barbara Feldon with costar Don Adams in Get Smart

John Cowsill best known for his work as a singer and drummer with his
siblings’ band, The Cowsells. He is currently a drummer and vocalist for
The Beach Boys touring band, which features original Beach Boys Mike
Love and Bruce Johnston. He also has performed and recorded with
Jan and Dean.

The Cowsills ( from left to right ) Paul, Barry, Bob, and John. The picture
is from 16 Magazine, 1970.

John Cowsill at work

Actress Tyne Daly is most widely known for her work as Detective Lacey in 
the CBS television series Cagney & Lacey (1982 – 1988). She has won six 
Emmy Awards for her television work.

Tyne Daly, left, with Sharon Gless in Cagney & Lacy

Daly was in Clint Eastwood’s 1976 film The Enforcer