The 60-year-old ITV star was back after her two months off, and spoke to Piers Morgan and Susanna Reid about Piers Corbyn's controversial interview on their show.
She branded Corbyn a "nutter" after he claimed the coronavirus pandemic was "invented" and modern day vaccines are "unnecessary".
The former Labour leader's brother argued that there was "no need for a vaccine whatsoever" as they are made to "make money for the mega corporations".
Lorraine told her ITV co-stars: "I was shouting at my television..."
Piers Corbyn left Piers and Susanna raging as he argued that the pandemic was a "psychological operation to close down the economy".
He told Piers and Susanna: "What we're doing is challenging the government to give actually evidence that there is a virus."
Piers raged: "You're suggesting the British prime minister invented having a virus that might not exist?"
Morgan was quickly cut off by Corbyn, before fuming: "Hang on, let me finish the question!"
Piers Corbyn shot back saying: "Don't interrupt me when I'm answering then."
Good Morning Britain's resident doctor Hilary Jones was also furious during the debate. He said Piers' comments are "extremely dangerous".
Jones fumed that Corbyn "shouldn't be on air" and he's talking "rubbish fake news".
Piers Corbyn was arrested and fined £10,000 for his part in organising Saturday's demonstration in central London against lockdown restrictions.
The weather forecaster and climate change denier insisted that Covid-19 didn't exist, claiming it had been around for 35 years as a type of flu.
Lorraine airs weekdays at 9am on ITV.