Following the mysterious defection of Cllr Theressa Bowen from Labour to the clutches of Pam Palmer's Independents just a few months after the last council elections, the two parties have been level pegging in terms of the number of seats held.
The history of politics is littered with defections, but this must be the first time anyone has ever changed sides while staying on the same side of the fence, and ever since the coalition has been like that bus at the end of The Italian Job - perched on the edge of a cliff with one sudden move likely to lead to disaster.
For reasons which are not yet clear, the Labour group is growing increasingly worried that the balance is about to be disturbed. Perhaps one of their councillors may be struggling to maintain their grip on their allotted perch, or perhaps there is a whiff of a looming resignation from the ranks.
Who knows, but Cllr Siân Caiach, the non-aligned councillor for Hengoed, has been approached twice in the last couple of weeks by Labour councillors wondering if she would like to come to the party.
The fact that she has called for Kev's resignation, and is normally regarded by the other parties as someone who is both radioactive and a carrier of the Black Death, tells us a lot about the state of morale among the Labour troops who know that Pam Palmer's battered old tank is primed to move onto Kev's lawn at a moment's notice.