Henry Muck, suitably nicknamed Prince Hal by his family and friends, may be Industry’s version of the ultimate privileged wastrel. He’s a member of the British aristocracy — a literal sir — who has convinced himself he can save the world with the green-energy company Lumi. He has also convinced a number of investors as well as management at Pierpoint & Co., where the HBO series’ main characters are tasked with managing Lumi’s IPO. The only problem is that...