LONDON, U.K. -- One, two, three, four. That鈥檚 how many British prime ministers have come and gone in the few years I鈥檝e been reporting out of London, all of them Conservative. It must be a record of some kind, achieved through fits of misjudgment, betrayal, conniving, conceit, and scandal at the highest level.

Remember David Cameron? He was the first to go, shamed into resignation over his Brexit referendum humiliation. The second was Theresa May, driven out of Downing Street by Boris Johnson, plotting and scheming with his allies. He was number three, in turn tossed out by a party tired of his self-inflicted scandals, his looseness with the truth and the Donald Trump-like chaos he seemed to promote.

So, to number four, Liz Truss, the new prime minister. If her name is new to many Brits, it鈥檚 entirely understandable.

She entered Oxford University as a Liberal Democrat from an active left-of-centre family. She even campaigned for a referendum to abolish the monarchy鈥攖o essentially jettison the same Queen who officially invited her to appoint a new government.

Her greatest rebirth was in joining the Conservative Party, which has certainly left herself open to attack as a leader who put opportunity ahead of principle.

Even then, her transformation wasn鈥檛 complete. She supported remaining in the European Union, that is until the country voted in favour of Brexit. Then, she changed sides.

鈥淚 was wrong,鈥 she later said. 鈥淚 am prepared to admit I was wrong.鈥 That, in itself, is a departure from Johnson鈥檚 defiant belief in himself.

As prime minister, Truss faces monumental challenges including a whammy of double-digit inflation, looming recession and rising energy costs that could force families to choose between buying food and heating their homes.

A fall and winter of discontent could be about to descend upon the country, and her first days in office may well determine if she becomes the next Conservative casualty.

Johnson doesn鈥檛 appear to be going away either. In his farewell to the nation, he pledged to support Truss, but he has vast experience in breaking pledges.

鈥淚 am a booster rocket that has fulfilled its function,鈥 he said during his final Downing Street address. In that speech, he described himself like Cincinnatus, the great Roman military leader who saved the state, retired to his farm, only to come back when Rome needed him again.

He now becomes Backbencher Boris, nursing resentment at a party that threw him out, hinting at his readiness to return should he get the call as Cincinnatus did.