join someone in or join someone on

[allthewayanime]

I would like to know when I have to use 'join someone in' and 'join someone on'. For instance:

e.g. Mike joined Maria on the show/in the show.

[5jj]

I would like to know when I have to use 'join someone in' and 'join someone on'. For instance:

e.g. Mike joined Maria on the show/in the show.

If Mike and Maria are both performers, then you can use 'om' or 'in'. If they are watching the show, then it's 'at'.

[allthewayanime]

Thank you.