Jonathan Smith is an angel sent down to earth "on probation". Jonathan and friend Mark Gordon 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 ethnicitys, 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.