The allegations against Hunter Biden have been generally consistent for years, dating back to when then-President Donald Trump dispatched his political bagman Rudy Giuliani to dig up dirt around the time Joe Biden announced his run for the White House in 2019.

The basic outline is this: Hunter Biden, while he was in the throes of a drug addiction that broke up his family, made millions of dollars from foreign companies because his last name is Biden.

While the basic storyline hasn't changed, there is an evolving series of disclosures, investigations and legal problems facing the president's son and causing grief for the president as the latter tries to convince Americans he deserves four more years.

Hunter Biden's attorney Abbe Lowell, who also at one time represented Trump's daughter Ivanka, dismissed the new details as "retread, repackaged misstatements of perfectly proper meetings and business by private citizens."

While it's true that there have been no criminal charges or allegations, even from Republicans, of something illegal, it's also true that none of these developments sound good:

►House Republicans are filling in some unflattering details about Hunter Biden's substantial income from foreign sources in the period before his father ran for president.

►Attorneys for an IRS whistleblower who allege there is political interference at the Justice Department in the Hunter Biden criminal investigation met with congressional investigators last week.

►An Arkansas paternity-related case has the potential to fill in details about income from his art career and help from wealthy friends in the period since his father became president. Hunter Biden has asked for his $20,000 per month child support payments to be lowered.

►A long-simmering federal criminal investigation could cause even more problems for the president's son if prosecutors ultimately decide to bring charges against him, potentially over alleged tax violations and making a false statement relating to a gun he bought. The investigation has examined the foreign business dealings that the GOP is focused on. But investigators and prosecutors have had trouble corroborating many of the claims and have focused their probe on Hunter Biden's tax issues.

►A new line of inquiry has to do with whether a sitting CIA employee interacted with former officials involved in an effort to downplay the discovery of a laptop tied to Hunter Biden and publicized before the 2020 election. Hunter himself is not implicated in that inquiry, but it is certainly part of the larger set of inquiries that stem from the president's son.

What no investigation has yet proven is any corruption related to the president and his son or any direct connection to the president at all -- although Republicans also allege there is paperwork regarding an interview conducted by the FBI with a mysterious witness Republicans are calling a whistleblower making allegations about Joe Biden during his time as vice president.

The FBI on Wednesday refused to provide the document, arguing that "unverified or incomplete information" could "harm investigations, prejudice prosecutions or judicial proceedings, unfairly violate privacy or reputational interests, or create misimpressions in the public."

How were Hunter and other Bidens paid by those foreign companies?

Even if there's no direct evidence of corruption, the money flowing to Hunter Biden, his uncle James and even his brother Beau's widow Hallie, with whom Hunter also had a relationship, does not paint a pretty picture.

They were paid millions through a series of companies, according to a new report, the second by the House Oversight Committee delving into the issue.

The report is being used by Republicans to allege that Hunter Biden, along with other Biden family members, turned the family name into a calling card for work abroad.

The committee presented redacted images of money transfers that it argues show how a company tied to a Romanian business executive, since convicted of corruption in his own country, paid a company tied to Hunter Biden's business partner. That company, in turn, paid certain Biden family members.

At a news conference announcing the new report, House Oversight Committee Chairman James Comer said he views this as an investigation not just of Hunter or other Biden relatives.

"I want to be clear," Comer said. "This committee is investigating President Biden and his family's shady business deals that capitalized on Joe Biden's public office and risked our country's national security."

In March, the committee detailed a similar arrangement, whereby a company with ties to Hunter Biden was paid by a Chinese company and then split the proceeds with Hunter Biden.

Comer said Republicans will push for legislation to require new disclosure of financial arrangements for elected officials.

A White House spokesman, Ian Sams, suggested Comer was only selectively releasing information and "spreading baseless innuendo." He also noted there is no evidence of any influence on Biden or Obama administration policy.

Side note on the financial arrangements of powerful people

Opaque business deals invite suspicion, but it's a little strange to see Republicans who defend Trump's business, which is divided into scores of companies, now attack the Bidens.

It is similarly hypocritical of Democrats who have attacked Trump to dismiss anything to do with Hunter Biden.

You've heard this story before

Republicans have been hammering away at versions of the Hunter Biden storyline ever since 2019, sure that the scent of scandal attached to the president's son will drag down his father.

Trump survived his first impeachment after trying to pressure Ukraine's president to investigate Biden.

Republicans in the Senate, when they held the majority there, issued a report on Hunter Biden -- although it alleged no specific corruption -- just before the 2020 election.

House Republicans, now that they have the majority, have taken up the baton.

Never a concrete allegation against the president

Senate Republicans failed to find direct evidence of corruption in the Bidens' activity in Ukraine in that 2020 report, although it allowed them to repeat that Hunter Biden's business career while his dad was vice president was awkward at best.

Republicans see laziness or worse in the lack of federal charges against Hunter Biden for either tax evasion or his gun purchase, but that could also be because there's not a sound case.

Not much is known about the IRS whistleblower that wants to share their story with lawmakers. Almost nothing is known about the mysterious FBI interview House Republicans have demanded to hear about.

Joe Biden has continued to defend his son

"There's not a single thing that I've observed at all that would affect me or the United States relative to my son Hunter," Biden told "60 Minutes" last September. More recently, he told MSNBC last week, "My son has done nothing wrong. I trust him. I have faith in him. It impacts my presidency by making me feel proud of him."

Now, as Trump and Biden prepare to run against each other (again) for the presidency, and with the focus on Hunter entering a new fever pitch, the question will be whether all the time and effort Republicans have invested investigating the president's wayward son will change the storyline.