Who were thrown into Nebuchadnezzar's blazing furnace?

Answer: Shadrach, Meshach and Abednego

Nebuchadnezzar had the furnace heated seven times hotter and threw Shadrach, Meshach and Abednego into it.

“At this, Nebuchadnezzar was filled with rage, and the expression on his face changed toward Shadrach, Meshach, and Abednego. He gave orders to heat the furnace seven times hotter than usual,”— Daniel 3:19 (BSB)