The subject will always come after the verb in such a sentence. There can also be an adverb. The introductory there doesn't fit grammatically with the rest of the sentence as we will find most other words do. There is some food in the refrigerator. Is is the verb.
Food is the subject.
In the refrigerator there is some food. Moving the prepositional phrase does not change the introductory there. Find the subject and verb in these sentences. There may not be time for an encore. In the mail box, there was no mail.