In 1973, having initially been a member of the audience at a concert by the Who at the Cow Palace in Daly City, California, he ended up playing drums onstage after the band's drummer Keith Moon passed out mid-show.

In the early 1970s, he moved to California, where he met his wife and life-time collaborator Robin Young at City College of San Francisco in 1978.

While on the West Coast, Halpin and his wife managed a new wave punk rock night club, The Roosevelt, before moving to Indiana in 1995 to pursue opportunities in the visual arts.

[1] On November 20, 1973, the Who were opening their Quadrophenia US concert tour at the Cow Palace in Daly City, a suburb just south of San Francisco.

About 70 minutes into the show, drummer Keith Moon, a heavy user of drugs and alcohol, began to falter during "Won't Get Fooled Again", then suddenly slumped over his drum kit, and was helped off by roadies while the other members of the band finished the song as best they could without him.

[4] The remaining three band members then played a short jam, before going into "See Me, Feel Me", without drums, with vocalist Roger Daltrey adding a tambourine for percussion.

The song received a huge response, and Pete Townshend apologized to the crowd and thanked them for putting up with a three-quarter-strength band, saying "I think it should be us applauding you".

In truth, Halpin was lacking practice and had not played drums in a year, but Danese attracted the attention of the concert's promoter, Bill Graham.

Less successful, however, was his contribution to the more complex "Naked Eye", and he struggled to provide the contrasting tempos, despite Townshend attempting to give him instructions.

The show ended after "Naked Eye", and Halpin took a center-stage bow with Daltrey, Townshend, and bass guitarist John Entwistle.