Why do Killua and Gon pretend not to know Hisoka in episode 50?

Question

In episode 50 of Hunter x Hunter (2011), Hisoka wants Gon and Killua to "Play dumb," and pretend not to know him.

Why? What's the purpose of Gon and Killua pretending not to know Hisoka?

Answer 1

If I remember correctly, Killua and Gon were kidnapped.

There are two things in play here.

The first is that they had rapport with Hisoka. This means that they could use him to their advantage later on, to break free, to take down a gang member, to get information from him, etc. If the gang was aware of this, they may intervene to stop this advantageous situation.

Second and more importantly, the gang members knowing that Hisoka knows them could be deadly for all three of them. The gang could interpret that as Hisoka being a traitor, or Killua and Gon being infiltrators. In either case, the gang would want to eliminate Hisoka, or Killua and Gon... or both.

So, due to their advantageous relationship and their potential threat to the gang's security, it was far more beneficial for all three of Hisoka, Killua, and Gon to pretend that they did not know one another.