Well done, I had to look at my notes because I couldn't even remember this one!
"Blondie" and Tuco aren't really friends but they work together.
Tuco changes his mind about letting "Blondie" die when "Blondie learns a secret from a dying man.
"Blondie doesn't trust Tuco, so he steals his gun before a shoot out and, later, leaves him tied up with his share of the gold.