The series stars Michael Landon as Jonathan Smith, an angel sent down to earth "on probation", and his human companion Mark Gordon, played by Victor French, Landon's co-star from Little House on the Prairie. Jonathan and Mark are given "assignments" by "The Boss" (God) where they are required to use their humanity (and sometimes a little bit of "The Stuff") in order to help various troubled souls to overcome their problems. Examples of these problems include families dealing with sick loved ones; wealthy and greedy businessmen being encouraged to use their wealth for good; and discouraging prejudice in regards to people of different ethnicities, appearances, or socioeconomic backgrounds or who have disabilities. While dealing with these situations with sensitivity, Highway to Heaven also used humor – particularly between Jonathan and Mark. Their personalities often clash (Jonathan being more sensible and compassionate but naive, and Mark being more pragmatic and cynical), but they always support each other. Jonathan's mission on Earth is to do enough good so that he could earn his wings and, presumably, ascend to heaven. Due to the close relationship that builds between Jonathan and Mark, this becomes a contentious issue as Mark does not want to lose his friend, and sometimes tries to prevent it from happening.