Sen. Lindsey Graham (R-S.C.) has been one of Donald Trump s staunchest supporters in public, but an upcoming book reportedly claims he was anything but during his secret testimony to a grand jury.

Graham turned on a dime and threw Trump under the bus during his testimony in the Georgia election subversion case, according to a Politico account of the upcoming book Find Me the Votes: A Hard-Charging Georgia Prosecutor, a Rogue President, and the Plot to Steal an American Election by Michael Isikoff and Daniel Klaidman.

The senator tried and failed to avoid testifying in the case, even appealing to the Supreme Court on the matter.

But according to the book, he was quite cooperative once he did turn up.

According to secret grand jury testimony in Fulton County confirmed by the authors, Graham testified that if you told Trump That Martians came and stole the election, hed probably believe you, Politico wrote.

The Atlanta Journal-Constitution had a similar report last year , saying Graham told the grand jury that if somebody had told Trump that aliens came down and stole Trump ballots, that Trump wouldve believed it.

The new book goes further, saying Graham also suggested to the grand jurors that Trump cheated at golf.

Graham met Fulton County District Attorney Fani Willis in a hallway after his testimony and gave her a hug, saying that was so cathartic, Politico added.

The former president was ultimately charged with 13 felony counts in the case, which is currently pending. Trump is facing a total of 91 felony counts across four different criminal cases.

The book hits shelves Jan. 30.