It’s the moment Westminster has been awaiting for weeks – Dominic Cummings will this morning give evidence to MPs which is expected to be highly critical of the government’s handling of coronavirus.

The appearance by Boris Johnson’s maverick former adviser is sure to offer political theatre.

And the personal beef that has developed between the prime minister and his former Brexit brother-in-arms Cummings adds to the drama.

Here’s what to expect from the lockdown-dodging ex-Downing Street supremo.

What’s happening? 

Cummings is giving evidence on Covid to a joint committee of MPs from the science and health select committees, chaired by ex-cabinet minister Greg Clark and Jeremy Hunt respectively.

The session is expected to last a mammoth four hours, giving TV broadcasters a tantalising dilemma over whether to switch away from Cummings to cover Johnson at prime minister’s questions.

MPs will quiz Cummings on four areas:

1. Pandemic preparedness and the first lockdown.
2. Non-pharmaceutical interventions such as Test and Trace and the effect the ex-aide’s infamous Barnard Castle trip had on public policy.
3. The vaccination programme.
4. Decision-making and controversy around the second lockdown.

Okay, sounds interesting, but why is everyone so excited?

Well, ever since Johnson effectively provoked war with Cummings by phoning newspaper editors to blame him for leaks against the government, the former adviser has been sharpening his tongue for revenge.

But many also feel that the testimony of such a senior figure in Downing Street’s response to the pandemic, who only left in December, could and should carry weight regardless of any ulterior motives.

While Cummings’ verbal evidence is expected to be enlightening, many will be looking to the texts, emails and other documents he provides to the committee for corroboration of his claims, given he may not be exactly the most trustworthy witness following the Barnard Castle “eye test”.

The ex-aide has promised to provide “the only copy of a crucial historical document from Covid decision-making”, and all eyes will be on this.

What will Cummings say?

Cummings’ communication skills are now well known, with his “take back control” mantra contributing to the Brexit campaign’s against-the-odds victory and being immortalised by Benedict Cumberbatch in a Channel 4 film.

And true to form, the former Vote Leave chief has spent the days leading up to the inquiry seizing control of the news agenda with an interminably long Twitter thread of his gripes and concerns, so we sort of know what to expect.

‘Herd immunity’ 

On the first lockdown, Cummings is expected to argue that the UK should have followed the lesson of Asian countries and locked down much earlier.

His central claim will be that government scientists like Patrick Vallance were instead pursuing a so-called “herd immunity” strategy to let the virus spread and minimise the chance of a second peak.

In an example of how outspoken he is likely to be, Cummings tweeted that behavioural scientists influencing policy in February 2020 “disastrously” made arguments against a lockdown “based on nonsense memes like ‘Asians all do as they’re told, it won’t work here’”.

Instead of locking down, the government wanted to allow Covid to spread but to “flatten the curve” of its growth in order to avoid a second peak, he will say.

Blaming pandemic planning which was “AWOL” and a “disaster”, he said:  “If we’d had the right preparations and competent people in charge, we would probably have avoided lockdown one, [and] *definitely* no need for lockdowns two and three”.

‘Bodies pile high’

Perhaps Cummings’ most damaging testimony will centre on Johnson’s personal conduct in the autumn when he overruled official scientific advice and declined to impose a short “circuit-breaker” lockdown.

ITV’s Robert Peston reported that Cummings will allege that Johnson said “Covid is only killing 80 year-olds” as he argued against imposing restrictions.

Several reports also suggest the PM did not want to repeat what he felt was a mistake in March by bowing to pressure to impose the first lockdown.

Cummings will allege that Johnson said he’d rather be like his “hero” – the mayor in the film Jaws who kept the beaches open despite evidence of a huge shark waiting in the water to eat people.

Cummings is sure to be asked if the PM said he would “rather see the bodies pile high” than later impose a third lockdown – comments denied by No.10 amid the briefing war between Cummings and his former boss.

But several journalists, including BBC political editor Laura Kuenssberg, have said they have sources corroborating the account and calling into question No.10’s denial.

There have also been suggestions that government officials are worried that Johnson will be accused of missing five key Cobra emergency committee meetings at the start of the pandemic because he was working on a book about Shakespeare – claims denied by No.10.

Cummings has also already accused Johnson of lacking “competence and integrity”, citing a “possibly illegal” plan for Tory donors to pay for renovations of the Downing Street flat he shares with fiancee Carrie Symonds, although this may not come up in the committee.

A hard rain’s a-gonna fall

True to form for an adviser that once terrified civil servants by promising a “hard rain” would fall on them while he was in Downing Street, Cummings has repeatedly criticised Whitehall’s response to Covid.

He has already blamed the “particularly awful” management of health officials for delays to mass testing despite clear advice from No.10 to treat it “like a wartime project”.

Health secretary Matt Hancock has also been accused by the ex-aide of presiding over a “smoking ruin” of a health department.

Not one to leave anyone out, Cummings has also turned his fire on the initial “secrecy” of advice from the Scientific Advisory Group for Emergencies (Sage), while suggesting that “deep institutional wiring” of political parties and the civil service “program destructive behaviour by putting the wrong people in wrong jobs with destructive incentives”.

How will Johnson respond and what impact will he have?

No.10 has so far been reluctant to engage with Cummings’ barbs, believing that the public are focused on the present success of the vaccine rollout and a future free of restrictions, rather than worrying about what happened in a year most want to forget.

But Labour leader Keir Starmer is sure to seize on Cummings’ evidence at prime minister’s questions, and it remains to be seen whether Johnson will be able to resist having a dig at his now-nemesis while he continues giving evidence.

Reports suggest Cummings wants Johnson out of No.10, but given a recent YouGov poll said only 14% of the public trust him to tell the truth about the pandemic response, he may have his work cut out.

The key could be in the written evidence, or if Cummings has damning recordings of the PM’s comments at the time.

But even then, the two select committees will control what is published and may hold back documents if they risk breaching the Official Secrets Act, or if they are unrelated to the inquiry.

Many may also ask what exactly Cummings was actually doing himself during the pandemic, as the most senior adviser in Downing Street.

And questions on whether his own lockdown-breaching trip to Barnard Castle undermined public compliance with restrictions could prove more than awkward.