This week it was announced that Irish actor Brendan Gleeson will play Donald Trump in an upcoming CBS mini-series. The script will be based on the memoirs of sacked FBI Director James Comey, who will be played by Jeff Daniels.

There may not have been any Hollywood stars on Capitol Hill this week, but there was still plenty of drama, with the ongoing impeachment inquiry delivering more plot twists than any TV mini-series.

Last weekend it emerged that a second whistleblower had come forward claiming to have firsthand knowledge of Donald Trump's dealings with Ukraine.

The US president said he wasn't concerned about this development. He told reporters that the impeachment inquiry is making it harder to do his job, but while few people could handle it, he said he was thriving on it.

The US Ambassador to the EU, Gordon Sondland, was due to testify before Congress on Tuesday as part of the impeachment investigation.

He had travelled to Washington from Brussels and was getting ready to give his evidence when the White House dramatically blocked him from testifying at the last minute.

Donald Trump tweeted that he would have loved to allow him give evidence, but "unfortunately he would be testifying before a totally compromised kangaroo court, where Republican's rights have been taken away, and true facts are not allowed".

Ambassador Sondland was one of a number of US officials who exchanged text messages discussing a White House visit and military aid for Ukraine in return for the opening of investigations. He is now expected to testify next week.

Democrats have issued fresh subpoenas for documents from the White House and the Pentagon relating to the freezing of military assistance for Ukraine.

Their lawyers were kept busy preparing many more subpoenas after the White House formally announced in recent days that it would not be cooperating with the impeachment investigation.

The US president’s lawyer wrote to senior Democrats describing their investigation as baseless, partisan and unconstitutional.

The letter claimed the inquiry was a violation of due process and was invalid because there has been no impeachment vote on the floor of the House of Representatives.

Responding, Speaker of the House Nancy Pelosi said it was the latest unlawful attempt to cover up Donald Trump's betrayal of democracy.

She warned that the US President is not above the law and would be held accountable.

There were similar calls this week from the Democratic frontrunner, and the focus of Donald Trump's corruption allegations, Joe Biden.

For the first time, we heard the former US Vice President call for impeachment.

"To preserve our constitution, our democracy, our basic integrity, he should be impeached", Mr Biden told supporters at a rally in New Hampshire.

Donald Trump responded by once again accusing Joe Biden of corruption, and claimed the Biden campaign was "sinking" and "falling like a rock."

Then came one of the week's most dramatic plot twists. 

Two associates of Donald Trump's lawyer, Rudy Giuliani, were arrested for campaign finance violations.

Lev Parnas and Igor Fruman were involved in attempts to investigate Joe Biden in Ukraine.  They were also linked to efforts to have the then-US Ambassador to Ukraine removed.  Marie Yovanovitch was recalled from her role in May.

In his controversial phone call with the President of Ukraine, Donald Trump described her as "bad news".

Marie Yovanovitch testified before Congress on Friday as part of the impeachment inquiry, and said she was "incredulous" that she was sacked over "unfounded and false claims by people with clearly questionable motives".

At a rally in Minnesota this week, Donald Trump said the impeachment investigation was a brazen attempt to overthrow the Government and would result in a political backlash against Democrats at the ballot box.

Right now, the latest opinion polls don't support that view.

A growing number of Americans are in favour of impeachment with just over half of voters wanting President Trump removed from office, according to a Fox News poll released this week.

It's Donald Trump's favourite TV network, but not even Fox is immune from his criticism when things don't go his way.

He tweeted that he has never had a good poll from Fox News. "Whoever their pollster is, they suck," he wrote.

President Trump watches a lot of TV and will lash out at any negative press. How will he react to a big-budget, high-profile mini-series based on his time in office?

Brendan Gleeson has starred in many Hollywood blockbusters, playing guards, priests, criminals and wizards, but this new role could be his most challenging yet.