Donald Trump’s “pitbull” Michael Cohen is meeting with House and Senate Intelligence Committee investigators today and tomorrow behind closed doors about his central role in the Trump-Russia scandal. Cohen is perhaps the figure in Trump’s orbit who most represents the cross-section between the Trump Organization and the Trump campaign’s desire to get closer to Russia.

American Bridge Rapid Response Director Emily Aden stated, “From expanding Trump’s business in Russia during the campaign to drafting a secret plan to lift US sanctions on Russia after Trump won the election, Michael Cohen is at the crux of the Trump-Russia scandal. Congressional investigators–and Special Counsel Robert Mueller–have their work cut out for them.”

Here are five deeply disturbing events that congressional investigators will surely press Michael Cohen on in their meetings:

1. October 28, 2015: Michael Cohen had Donald Trump, already a presidential candidate, sign a Letter of Intent to build Trump Tower Moscow with Moscow-based developer I.C. Expert Investment Co.

2. November 3, 2015: Michael Cohen received an email from Trump aide and Russian mobster Felix Sater saying of Donald Trump “Our boy can become president of the USA and we can engineer it,. I will get all of Putins team to buy in on this, I will manage this process.”

3. January 2016: Michael Cohen emailed Vladimir Putin’s spokesman Dmitry Peskov asking for help to advance the Trump Tower Moscow Project.

4. June 2016: Michael Cohen, while serving as a top Trump campaign surrogate, was invited by Felix Sater i to the St. Petersburg International Economic Forum and was promised introductions to top Russian government officials.

5. January 27, 2017: Michael Cohen, Felix Sater, and Ukrainian politician Andrii Artemenko wrote a plan to resolve the Russia-Ukraine conflict and lift US sanctions on Russia which Cohen reportedly delivered to then-National Security Adviser Michael Flynn. Donald Trump’s first official call to Vladimir Putin as President took place the next day.