Dark Towers (1981)

Stars:

Juliet Hammond, Sean Barrett, Christopher Biggins

Tracy follows her dog Towser into the overgrown garden of a strange old house, Dark Towers, and meets the impoverished Lord Dark and his son Edward.

Here is the link to the TV show at the Internet Movie database: http://www.imdb.com/title/tt0140734/?ref_=fn_al_tt_1