Watch this Guardian video to learn why is it important to target kleptocrats' money overseas.
Amid the recriminations over the Sergei Skprial poisoning, questions have been raised about how the UK government deals with Russia. Is expelling diplomats enough? Or would clamping down on the use of offshore accounts and money laundering to invest in London properties hurt the Kremlin more? Owen Jones takes a bus trip around London to find out.