Dominic Cummings is out as Boris Johnson's top aide

Dominic Cummings left Downing Street on Friday with a box of possessions, bringing his tumultuous tenure as U.K. Prime Minister Boris Johnson's top adviser to a sudden end amid a bitter power struggle among Johnson's aides.

Why it matters: Cummings came to national attention as the director of the successful "Vote Leave" Brexit campaign. Since entering Downing Street he's been depicted in somewhat Machiavellian terms — as the power behind Johnson's throne. He also caused a national uproar in May by declining to resign after breaking lockdown rules.

Update: While the BBC reports that Cummings was told to leave Downing Street "with immediate effect," multiple outlets have reported that he'll officially remain in his post until mid-December.