If you've watched the news this week, you've seen the powerful reunions.

Hostages, some taken years ago, finally back with their families. Israel and Hamas have both released captives, to long-awaited hugs, tears, and relief.

But these moments don't come easy. Negotiations are fragile and hard-fought - when every message, every word, carries the weight of human life.

World leaders have fronted the cameras, but who actually makes these deals happen?