WASHINGTON (AP) — Donald Trump said he had a secret.

He dangled it on Twitter. He parried reporters’ questions about it. He milked the moment, drawing out the drama for weeks.

That big tease played out in 2011, when Trump promised to reveal what his private investigators had found in Hawaii about President Barack Obama’s birth certificate. (Trump never did release anything.)

Now, Trump has stretched out a new high-stakes guessing game, this time in the White House, by hinting that he might have recordings of his conversations with fired FBI Director James Comey.

Trump is expected to answer the tapes question this week.

If they do exist, they could become a central piece of evidence in the Russia investigation that has transfixed Washington and cast a shadow over the future of Trump’s presidency. If they don’t, questions will be raised about why the president would stake his reputation and political capital on promoting something that just isn’t real.

Several outside advisers who speak to Trump regularly said the president has not mentioned the existence of tapes during their conversations. White House aides have been known to grimace when the subject comes up, and more than a half-dozen staffers said they were unaware of any recording devices. All demanded anonymity to speak about private discussions with the president.

Whether the tapes exist or not, this is far from the first time that Trump, the former star of reality TV and tabloids, has manufactured a melodrama that begins with bluster but often ends with a whimper.

“I think he was in his way instinctively trying to rattle Comey,” says former House Speaker Newt Gingrich, a longtime Trump confidant. “He’s not a professional politician. He doesn’t come back and think about Nixon and Watergate. His instinct is: ‘I’ll outbluff you.'”

The latest chapter in Trump’s tale of mystery began last month, just days after he fired Comey, then leading the investigation into contacts between the president’s campaign and Russian officials.

A New York Times report cited two unnamed Comey associates who recounted his version of a January dinner with the president in which Trump asked for a pledge of loyalty. Comey declined, instead offering to be “honest.” When Trump then pressed for “honest loyalty,” Comey told him, “You will have that,” the associates said.

Trump tweeted the next day that Comey “better hope that there are no ‘tapes’ of our conversations before he starts leaking to the press!”

That immediately evoked the secret White House recordings that led to Richard Nixon’s downfall during Watergate. Under a post-Watergate law, the Presidential Records Act, recordings made by presidents belong to the people and can eventually be made public. Destroying them would be a crime.

Comey has claimed that any recordings would support his claims that Trump asked him to pledge loyalty and to drop the investigation into Trump’s former national security adviser.

“Lordy, I hope there are tapes,” Comey declared at a congressional hearing.

But the president has steadfastly refused to clarify whether any tapes exist.