Peter was born in 1955 in New York to Tom (an advertising executive) and Mary (a bacteriologist), an Irish Catholic family.
He attended Byram Hills High School in Armonk New York, and then Tufts University, graduating in 1977, and while there sung with the Beelzebubs.
Interested in acting since his days of school plays and musicals, he made his professional debut in Hair in 1977.
As well as small and big screen acting, Peter is also an acclaimed stage performer and singer.
He is married to music Video producer, Paula Harwood since 1983, and has two children: James and Kathryn. As of 2007, they live in New York.