Singular subject followed by verb without "s"

This is the sentence I wish to construct:

When the show finishes, someone remind the ice-cream man to start
picking up the garbage.

The verb in question is "remind". Should it be "remind" or "reminds"?

I have a hunch that it should be "remind". If so, why is the subject and verb not in agreement? (Normally "someone reminds" is considered correct.)

Is there a grammatical term to describe this type of usage? Any reference would be helpful too.

Thanks

Answer

It depends. Is it meant to be issuing a directive? If so, your example would be correct ("someone" + infinitive).

However, if it is stating what happens, then you would have to use "reminds" ("someone" + he/she/it form of "remind") since the pronoun "someone" describes an "it"; an unknown/unspecified person.