Heather O’Rourke and Zelda Rubinstein are the only players from the first two films to cross over into the light of Poltergeist III. Here, O’Rourke’s character, Carol Anne, seemingly dumped by her parents for reasons unknown, is taken care of by her Aunt Patricia (Nancy Allen), Uncle Bruce (Tom Skerritt), and teenage step-cousin, Donna (Lara Flynn Boyle), living in a high-rise building in Chicago. Carol Anne has been enrolled in a school for gifted but troubled kids, as her therapist, Dr. Seaton (Richard Fire), thinks that the young girl has the ability to hypnotize people into believing her delusions about seeing ghosts. Seaton forces Carol Anne to speak about her experiences, which brings to light her involvement with the dreaded Reverend Kane (Nate Davis), and this talk has caused the late Reverend to cross over into trying to get in contact with the girl again. For some reason, the entire building is chock full of mirrors at every turn, which is convenient to the haunting that emerges, as most of its haunting involved scaring the bejeesus out of the family and their cohorts through reflections in whatever mirrors they happen to be looking at.
The film starts out with Jake Blues (John Belushi) being released from prison, picked up by his brother Elwood (Dan Aykroyd) in a used cop car turned “Blues Mobile”. They make good on a promise to visit the orphanage they grew up in, only to find it is in danger of being shut down, due needing $5,000 in tax money owed. With only days to go before it is too late, the Blues Brothers are inspired by a vision from God to save the orphanage, which they plan to do by reuniting the band they played in. This proves to be a tough task, as all of the members have moved on to other occupations. Not only this, but along the way, they manage to piss off the police, the Illinois Nazi Party, and just about everyone else they come across in their bid to make enough money to deliver by the deadline without getting caught, or worse.