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Theo's Adventure Capitalists 8pm, BBC2 Theo Paphitis takes a break from lounging conceitedly in the Den's leather chairs to give "I-told-you-so" advice to three British entrepreneurs riskily setting up abroad. Amid unapologetic schmoozing and boozing, Paphitis oversees this episode's companies – publishers Haymarket, a luxury yacht agency, and a duo looking to set up an international school – as they try to wangle profitable business deals in beautifully filmed Vietnam. The Story Of Science – Power, Proof And Passion 9pm, BBC2 What is the world made of? In order to answer this question, says Michael Mosley, you have to realise that "nothing is really solid" and "we consist almost entirely of empty space". That'll be quantum physics he's talking about, then. As to how we reached our understanding of the world's intrinsic weirdness, it's a story that Mosley traces largely via the history of chemistry. It's a discipline that has its roots in the work of alchemists, whose experiments included boiling down urine, a process that evidently smells even worse than you'd imagine, yet has a "phantasmagorical" pay-off. Luther 9pm, BBC1 Idris Elba in his best post- Wire role to date. He's DCI John Luther, a detective coming back from gardening leave after a controversial case to investigate a baffling double homicide. The occasional generic note in the storyline (he's a maverick but his boss is still happy to bet on him, etc) doesn't deter from what is essentially a very enjoyable opening to this moody six-parter. Good support too from Ruth Wilson as physicist/femme fatale Alice Morgan (specialist subject: dark matter), and Indira Varma as Luther's estranged wife Zoe. Sea Fever: For Those In Peril 9pm, BBC4 Part of a series exploring our relationship with the sea, as the title suggests, this programme focuses on those people who perform the vigilant and often dangerous task of rescuing those who've ended up in the drink without planning to. We meet Peter Halil and Gerry Douglas Sherwood, former lighthouse keepers who shot powerful video memoirs of their now all-but-automated way of life, and RAF winch man Eric Smith, who won the George Medal for the 1962 rescue of two French trawlermen from a capsized boat. True Stories: Erasing David 10pm, More4 This social experiment by way of a documentary is an inventive and amusing way of tackling a serious point: the erosion of civil liberties in the UK. David Bond embarked on his project after being affected by the Child Benefit Office's loss of just two data CDs – meaning his address, bank details and date of birth were at large, along with those of 25 million other people. Here, he attempts to live away from public records for a whole 30 days, while tracked by private investigators – not an easy mission, considering Britain is behind only Russia and China in terms of surveillance. Its lack of worthiness and eye for humour make it even more effective at emphasising its point. La La Land 10.30pm, BBC3 Episode two of the stunt show that starts out innocuously enough but soon accelerates to the point where you can scarcely believe what's taking place. Marc Wootton is seemingly never happier than when there's a real chance of being lamped out cold by whoever he's suckering. "You are in the wrong fucking industry if you think you're going to succeed in any way, shape or form," wannabe actor Gary Garner is informed after one run in … and that's one of the politer comebacks. Genius.