(CNN) -- Ashton Kutcher's quiet romance with Mila Kunis has reportedly blossomed into an engagement. The former "That '70s Show" co-stars have never been shy about PDA since they began dating in 2012, but neither one has talked much about the relationship. Reps for both actors have been mum, with only a telltale photo of a diamond ring on Kunis' left hand to fuel speculation she and Kutcher will soon be tying the knot. But how did these two go from friends and co-workers to a couple? Here's a recap of the love story: 1998: Kutcher, then 20, landed a role in "That '70s Show," the Fox comedy about a high school kid growing up in Wisconsin during the late 1970s. Kutcher was the ditzy pretty boy Kelso, and Mila Kunis, at 15, was Kelso's on-again, off-again girlfriend, Jackie.
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Ashton Kutcher and Mila Kunis are reportedly engaged
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The two first met in 1998 on "That '70s Show"
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They say they have been friends for years
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When they began dating in 2012, they initially said they were just friends
While @placeholder insisted she was having a hard time finding a date in July 2012, paparazzi photos told a different story.