You'd be hard pressed to find a more romantic engagement story than the one George Clooney told on The Ellen DeGeneres Show.

The 54-year-old actor said he knew six months into his relationship with Amal that he wanted to marry the civil rights attorney. "I plotted the whole thing out," Clooney recalled of his proposal. "I had the ring hidden behind her. I had music playing. ...Everything was planned out and I've cooked dinner."

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However, not everything went as planned. "[Amal] comes in and she's just come back from London. Usually, she'll dress up and now she's like, 'Maybe we'll just order in.' I go, 'No, no, no I've made dinner.' I've got it all set up, timed out and the song is coming and she gets up to go wash the dishes, which she's never done," he explained. "And I'm like, 'What are you doing?' and then she comes back in."

While she threw a few hurdles at him, Clooney still managed the perfect proposal. "Finally I said [that] I blew out the candle and I think the lighter's in the box behind you. And she reaches around, pulls out the box and I've got just the ring sitting in there. She pulls it out and she looks at it and she's like, 'It's a ring,' like as if somebody had left it there some other time," he told DeGeneres. "I'm doing all the moves you can do with my face. I got down on my knee and said, 'I couldn't imagine spending the rest of my life without you.' And she kept looking at the ring and she was looking at me and she was like, 'Oh My God.' And we now know, because there was a playlist [and] we know how long it actually took, it was like 25 minutes."

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Of course with Clooney, his proposal story wasn't without a few jokes. "Finally, I literally said, 'Look, I hope the answer is yes but I need an answer. I'm 52 and I could throw out my hip pretty soon,'" he quipped. "And she said, 'Oh, yes.' It worked out really well."

Wednesday was Amal's 38th birthday, and when ET caught up with the Clooneys at the premiere of Hail, Caesar! on Monday, the actor was hesitant about inviting his handsome co-star, Channing Tatum, to his wife's birthday celebration. Both men agreed that it would be a bad idea for the Magic Mike XXL star to pop out of the cake. "I'd like to stay married," Clooney joked. "Stay away from my wife, man!"

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