Helium, the next financial crash and tipping

Will we run out of helium? Are soaring stock markets about to plummet? And should we replace tips with a compulsory service charge? Olly Mann and TheWeek delve behind the headlines and debate what really matters from the past seven days. With Harriet Marsden, Jamie Timson and Felicity Capon

Image credit: Archivio Camera photo Epoche / Getty Images