Every Monday, a group of unlikely bedfellows meet in Jeremy Corbyn’s parliamentary office. Jo Swinson, Liberal Democrat leader; Ian Blackford, the SNP’s Westminster leader; Caroline Lucas, the Green party’s sole MP; and Liz Saville Roberts from Plaid Cymru all gather to discuss their common aim — preventing a no-deal Brexit. This rebel alliance is more than just a group therapy session: last week, they succeeded in taking control of parliament and immediately started to give instructions to the Prime Minister.