The day has come for former President Lee Myung-bak to face investigators at the Seoul Central District Prosecutors' Office.
Lee, who served as president from 2009 to 2013, becomes the fourth South Korean leader to appear for questioning as a suspect in a criminal case.
Here's a wrap up of the major charges he's facing.
Evidence shows the former president received at least one.six-three million U.S. dollars of illicit money from the National Intelligence Service, and had it sent to the presidential office through his key aides.
Prosecutors also suspect he received over two million dollars from former CEO of Woori Financial Group Lee Pal-seung, some of which was put toward Lee Myung-bak's 2007 presidential election campaign.
Then there's the corruption-ridden auto parts company-- DAS.
Although documents point to his elder brother, prosecutors have concluded the company's 'real owner' is Lee Myung-bak and that he holds over 80 percent of DAS shares under various fake names.
One of the major allegations include Samsung Group paying over five-and-a-half million dollars in legal fees to a U.S. law firm to cover DAS' legal costs.
Investigators also identified slush funds totaling to more than 28 million dollars managed by DAS between 2003 and 2008. A large part of those funds are believed to be managed by Lee Myung-bak and his family.
The net also appears to be closing in around Lee's family members.
They interrogated Lee's brother and DAS chairman Lee Sang-eun, who was also the primary target of the DAS investigation.
So was Lee Myung-bak's son Lee Si-hyung-- an executive of the company.
Meanwhile, Lee's eldest brother and former lawmaker Lee Sang-deuk was summoned for bribery allegations, mainly on receiving dirty money from the intelligence agency and Lee Pal-seung for the ex-president.
Also accused of bribery, Lee's son-in-law Lee Sang-joo-- an executive at Samsung Electronics and husband to the former President's eldest daughter.
Both have admitted to some of their charges.
But the former president's charges extend beyond bribery.
Lee Myung-bak faces additional charges related to violation of law on the management of presidential records and violations related to election law.
He's expected to continue to deny all the allegations during his interrogation.
Park Hee-jun, Arirang News.