Sen. Lindsey Graham said on Saturday that once Americans hear the testimony of three State Department survivors of the Sept. 11, 2012 attacks on the U.S. diplomatic mission in Libya next week, “it’s going to make you mad. It’s going to make you upset.”

“Come Wednesday, you’re going to start hearing the truth about Benghazi,” the South Carolina Republican told former Arkansas Gov. Mike Huckabee on his Fox News program.

“Our people were abandoned. They were denied assistance,” Graham said in an interview via satellite from Greenville, S.C. “And what you were told by this administration after the fact was a complete political smokescreen.”

On Wednesday, the House Oversight and Government Reform Committee — chaired by GOP Rep. Darrell Issa of California — will hold widely anticipated hearings on the Sept. 11 attacks at the consulate in Benghazi.

Ambassador Chris Stevens and three other Americans, including two former Navy SEALS, died in the assaults.

The career State Department employees — self-described Benghazi “whistleblowers” — are scheduled to testify. Their names were disclosed in news reports earlier on Saturday.

They are Gregory N. Hicks, a foreign-service officer and former Deputy Chief of Mission-Chargé d’Affairs in Libya; former Marine Mark I. Thompson, the State Department’s acting Deputy Assistant Secretary for Counterterrorism; and Eric Nordstrom, a diplomatic security officer and former Regional Security Officer in Libya.

Nordstrom was the top security officer in Libya in the months leading up to the attacks.

Graham told Huckabee that Hicks was Stevens’ deputy and that “he was on the phone with Chris right before he died.”

The senator added he and Hicks have been discussing Benghazi for about two months.