When Loki came to the city of the Frost Giants, he took off the falcon suit. He walked and walked until he came to Thrym's house. Thrym was the giant who took the hammer.
Thrym was sitting on the porch, making gold collars for his dogs.
When he saw Loki, he said, "What do you want?"
Loki said, "I have come for the hammer."
The old giant laughed and said, "You will never get that hammer. It is buried eight miles deep in the ground.
"But there is one way you can get it. I will give you the hammer if you get Freyja for my wife."