I watched this movie during Nippon Connection Film Festival 2020 (online), and I had a hope in the name of Sabu. But it was a big mistake. The story is neither new nor interesting nor funny, although it was labeled as comedy or black humour. The stories/movies about ghosts which dwell on Earth unable to go to another world are ten a penny. Why to make movie about it again? Where is the new approach, compelling story, likable charakters?
Also I couldn't help but think: Sabu should stop watching the movies and series written by Neil Gaiman and never again try to write about spiritual stuff.
I found nothing good about "Dancing Mary". The story is corny and convoluted, some moves of charakters were not logical, or they changed their mind out of sudden. Also some of setting was barely believable (like the scene in hospital). Many scenes were unnecessary long, which is an common problem with japanese movies, this made movie running time too long as well.