Isaiah Washington promised fans of Grey's Anatomy that his return to the show in May will be epic.

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"I read the script last night," Washington told Access Hollywood Live. "The script is so amazing... it will blow you away... I was not expecting this."

The 50-year-old, who stars on The CW's The 100, also commended the show's creator.

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"Shonda Rimes is genius and something happens when she and I get together," he said. "I'm unbelievably humble and over the moon with what I read last night."

"I had to stop and say, 'OK, now what? What is the world going to do after this?'" he continued. "It's going to blow you away!"

Washington was written out on the season 3 finale in 2007 after his character Preston left Cristina (Sandra Oh) at the altar. His upcoming appearance will play a significant role in the departure of Oh's character at the end of the season.

He was let go from the ABC show that season after he allegedly used a homophobic slur to refer to his former and openly gay costar T.R. Knight. The incident occurred while he engaged in an argument with his other co-star Patrick Dempsey.

During an interview that year, the actor defended himself and said that he never used a derogatory term against Knight.

"I used the word during a disagreement with Patrick," Washington told the Houston Chronicle. "I apologized for that. We shook hands and went back to work."

He added: "I knew T.R. was gay, but I would never attack him because of his sexual orientation. That's stupid. I've been working with lesbians and gays for 21 years in this business."

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