(I'm new to TV Tropes, so I'm not too sure how these things work? But I made an account because it was bothering me enough that I couldn't find this trope anywhere — so feel free to help me out!)
That thing where there are a bunch of people trapped in a house — either ACTUALLY trapped (are not physically able to leave), trapped by responsibility (can't leave without arousing suspicion), or socially trapped (can't leave without messing up their social circle.)
Each person in the house has something different going on in their head and different motives for being there. The different characters proceed to run around the house doing different things for different reasons. Sometimes there are people in the house who only some of the other characters in the house know about. TV episodes with this trope are usually quite painful to watch, because they almost always involve severe misunderstandings.