At a conference, a talk can be done by a speaker (person) or multiple speakers (group of persons).
At a festival, a live set can be played by an artist (person) or a band (group of persons)
What's a word that would fit the following sentence regardless of the talk/set being done/performed by a person or a group?
The ____ will be on stage at 2PM on Thursday.
I've thought of “performer” but it wouldn't fit for a group.