The Bay was built in 1948 and was open through the years until 2014 or so. It is now a church.
Caseville is a small community on the northwest side of Michigan's Thumb. My sister remembers our dad telling her about building a theater for Johnson Construction Company there. We're assuming that it was the Bay Theatre at 6750 Main Street. The building still stands.
The Cinema Treasures website says that the theater opened in 1948, seated 360, and is now closed. It most recently was being used as a house of worship. With no Johnson theater slides or vintage images available online, we can only look at the building today and try to imagine when it was an entertainment focal point for the community. If any Michigan History group members in the Thumb have any old images of the Bay Theatre that they'd be willing to share, it would be great to see them!
In the Google Maps image, you can see that the south side of the building has been decorated with several Hollywood icons. The front of the theater has had another structure added to it to serve as an eatery. Another image on the north side of the building shows a marquee and entrance that appear to have been added recently.