Something along the lines of the Running Man, but different.
The story follows at least two characters set (in the future? alternate world?). One seems a good fellow: hard-working, earnest, cares for others. The other is greedy, won’t stop at anything to get his way.
They are both in ‘the game’. Born and bred for it, it’s all they know. People on the outside are watching (sci-fi then, television). It’s a massive competition, though people quickly get weeded out. It’s puzzles, obstacle courses, and more. Be fun to come up with some of the situations and how they get through them. The second guy cheats as much as possible of course.
It becomes very cut throat at the end. The reader learns the winner gets untold glory, power, money, freedom.
In the end the cheater wins. He is taken, given a fine bath and massage, excellent food and wine. He waves to the masses still trapped in the game, then is escorted into the building. Within it he learns his ultimate fate: live execution before the watching masses, something those on the inside never know happens.