Billy is an American sitcom and a spin-off of Head of the Class that aired on ABC for half a season from January 31 to May 30, 1992.
Following the end of Head of the Class, Billy moves to Berkeley, California, after Filmore High School was closed down, where he marries Mary Springer (played by Marie Marshall), a single mom with several children, so he could get his green card.
The marriage is arranged in order to prevent Billy from being deported back to the U.K. Billy becomes Mary's boarder, living in her basement apartment with the strictest of rules: no drinking, no smoking, no pets, and no sex.
The series follows Billy's misadventures as he adjusts to life in California while staying one step ahead of immigration officials seeking to prove his marriage is a sham.
Meanwhile, his relationship with Mary's children, 14-year-old David, 10-year-old Laura and 5-year-old Annie, (played by Johnny Galecki, Natanya Ross, and Clara Bryant) deepens to a parental level, and Billy and Mary likewise find themselves drawing closer together, although the series was cancelled before this subplot could be carried out.