Dominic Cummings' gradual reveal of what was in that box

Dominic Cummings carried a cardboard box as he left No 10 in November 2020

Since leaving Downing Street in the depths of winter, clutching only a cardboard box, it's been obvious that Dominic Cummings took something else with him when he departed.

That would be his version of everything that had gone on during the extraordinary challenges of the Covid emergency, which in an organised and gradual way he has started to reveal.

But his publication today of private messages between himself and the prime minister is a marked rise in the pressure he seeks to put on No 10.

• PM brands Hancock hopeless in texts revealed by Cummings

• Hancock defends not bringing in earlier lockdown

• Dominic Cummings' explosive claims to the MPs' committee

The exchanges, not denied by Downing Street, suggest the depths of Boris Johnson's frustration with Health Secretary Matt Hancock during the crucial opening weeks of the pandemic.

And that in the midst of emergency he contemplated sacking him from that position and installing Michael Gove.

But he then didn't act, and allowed someone he'd described as "hopeless" to stay on.

Given the former adviser's own chequered reputation, there's no sense right now that Downing Street will feel the need to act.

But the man who did so much to bolster Boris Johnson's position is providing regular and dramatic ammunition for his political enemies.

And there's no sense that No 10 can be sure that Mr Cummings' revenge is spent.