We all agree lying is shameful. Yet we still deliberately deceive each other constantly. Are our brains wired for lying from a young age? The brains of pathological liars may provide insights. Will technology make it easier for us to be dishonest, or could it someday instantly reveal someone is lying? Perhaps we are deceitful because our limited senses prevent us from seeing the real truth. Scientists say our own memories deceive us, and have managed to implant false memories. Other scientists look for ultimate truth in the subatomic world … only to end up turning reality on its head.

In a world where nothing seems to ever work out as you had hoped, The Rehearsal features Nathan Fielder helping ordinary people rehearse difficult conversations or life events through the use of sets and actors hired to recreate real situations. The situations can be trivial, like confessing to a lie about educational history, or more complex, like raising a child. Fielder commissions extravagant sets with every detail recreated. He hires actors to inhabit these sets and practice different dialogue trees with his clients dozens of times. Information used to train the actors and build the sets is often collected without the subjects' knowledge.
In the firs episode, Nathan Fielder helps Kor Skeete, a Brooklyn-based trivia aficionado who wants to confess to his bar trivia team that he lied about having a master's degree. Nathan reveals an elaborate method of rehearsals involving an actor (K. Todd Freeman) playing a 'fake Kor'. To help Kor rehearse the difficult conversation with his teammate Tricia to clean this long-held lie, Nathan creates simulations of trivia night with a fake Tricia in a full-scale replica of the Alligator Lounge, a Brooklyn bar. Kor overcomes his fears and makes his confession to the real Tricia.

To help Andrew in his search for love, relationship specialist Jodi Rodgers has come to work with him - on his dating skills. Olivia hasn't given up in her search for love. Today, she's on her way to meet someone new. She's meeting Jackson. Jackson likes origami and the smell of perfume. He hates the sound of nails on a blackboard and people slurping their tea. Jimmy and Sharnae are arriving at the Gold Coast for their first-ever holiday together. And Jimmy has a surprise in store for tomorrow.

Olivia meets someone who seems to truly get her. Andrew has found out about a speed dating event being held in town. He works on his jokes and James Bond impersonations before going to the dinner. Jimmy and Sharnae go on a special holiday together where Jimmy plans a romantic surprise.

If you had less than one second to make a life-or-death decision to shoot a man who might be armed with a lethal weapon, what would you do? Would the ethnicity of the man affect your decision? Are you sure? The outcome – whatever your race – will surprise you. Brain imaging studies are showing that negative cultural stereotypes hijack everyone’s subconscious decision-making. But some science says we can overcome bigotry through exposure, self-awareness and flexible social networks… and, most controversially of all, ultra-violent video games!

We now know that the brain - the organ that more than any other makes us human - is one of the wonders of the universe, and yet until the 17th century it was barely studied. The twin sciences of brain anatomy and psychology have offered different visions of who we are. Now these sciences are coming together and in the process have revealed some surprising and uncomfortable truths about what really shapes our thoughts, feelings and desires. And the search to understand how our brains work has also revealed that we are all - whether we realise it or not - carrying out science from the moment we are born.