Prime minister's questions is supposed to be a gladiatorial clash of the titans, in which the PM and the leader of the opposition trade blows over the issues of the day in a battle of wits.
This week's session proved a real advertisement for the session. It often comes under repeated criticism from those who don't like to see politicians behaving like children. But today Miliband and Cameron set aside trivial pettiness to send repeated blows against each other on the biggest issue of all, the economy, in an unusually passionate and pugnacious exchange.
The Labour leader appears to be setting aside his rather lumbering, slow-blinking approach to the sessions to inject some real feeling into his delivery.
Miliband's final attack against Cameron, in which he poured scorn on a "totally out of touch" prime minister, was a masterclass of controlled fury. Cameron glared back, meeting Miliband's spitting stare as he leaned over the despatch box down at the prime minister. It was an electric moment of tension.
The PM growled back in response, saying Miliband had "a lot of nerve" to go on the offensive in a week when Labour had appointed a former tax exile to run its election campaign.
This was the moment when Balls took the baton from his leader. As soon as Miliband had sat down for the last time, his shadow chancellor took over the show.
As anyone who has seen Balls lurching around on a football pitch knows, he is an expert at insinuating himself into positions where he should not by rights be. Like stealing the show at PMQs, for example.
Yet this is exactly what the shadow chancellor now proceeded to do. He began gesturing to Cameron to 'calm down', holding his hand down and gently patting downwards.
Once Cameron had calmed down, he resumed his other hand movement of choice. Balls has adopted the infuriating habit of making a side-to-side 'flatlining' gesture with one of his hands. This serves as a gentle reminder to government MPs that the economy, far from prospering, is stagnating without any meaningful growth whatsoever.
Doing so, the shadow chancellor has reduced the art of opposition down to a simple mime act. Whenever the economy is mentioned, he raises his arm and begins this sideways manoeuvre. The smug look on Balls' face as he does so is enough to send Tory MPs into spasms of rage. They despise him.
So does the PM. We know this because, after a quarter of an hour or so of being distracted from answering questions by the Balls mime act, he eventually snapped. "The shadow chancellor is wrong, even when he's sitting down," Cameron seethed, steam emitting from his suit as he fumed. "He talks even more rubbish when he stands up!"
Any political innovation, like the Balls gesture, soon gets a rise out of creative-thinking opponents. Yesterday in Treasury questions Tory MPs' riposte was to simulate an aircraft taking off with their hands, demonstrating that the economy is growing, after all.
Today the response appeared to be one of straightforward mockery. Sir Peter Tapsell, the Father of the House, derided the shadow chancellor's "increasingly maniacal gesticulotions", to hearty laughter from all quarters.
Only at the end did Cameron come up with a decent comeback, belittling Balls' antics by describing them as "rather questionable salutes".
This was good, but nowhere near enough to deter Balls from continuing. He proceeded to do so - now with an even wider grin across his mouth.
This was his triumph. The shadow chancellor had not uttered a word which will make it on to the official record, but this PMQs was his and his alone.