Note: Googling is encouraged as there are a lot of names in this puzzle - I apologize for the subpar fill... hope the payoff is worth it!
Hint #1: some solvers love them, some solvers hate them... rebus squares! but these aren't just ordinary rebuses
Hint #2: the rebus squares are bidirectional and contain characters from a TV show as well as a part of a plant
Hint #3: what is the shared surname of the TV show characters? (not the surname of the actors)
Hint #4: the band's name of the meta answer song is the answer to 41-Down