"Spin City" star Charlie Sheen is dizzy over a beauty who captured his heart right on the set of his show.
Sheen has taken a shine to gorgeous actress Denise Richards, his co-star for five episodes of the ABC comedy this season.
"Charlie is crazy about Denise," an insider told The ENQUIRER. "He's really fallen hard for her.
"His dad Martin, the star of 'The West Wing,' even came to the 'Spin City' set to meet Denise. Martin is thrilled his son is so happy.
"This is Charlie's first serious relationship in years."
Charlie, 36, and 30-year-old Denise -- a former "James Bond" stunner -- first met in June 2000 when they worked together on the movie "Good Advice."
"Charlie liked her back then but she had a boyfriend so nothing happened," said the insider. "Then Charlie recommended her for a guest spot on 'Spin City' this season -- and she was so good that one episode turned into five."
Once they were face-to-face again, Sheen was quickly smitten.
"Charlie says she is so beautiful that when he acted in scenes with her he had to stare at her forehead because her beauty destroyed his concentration!" revealed the insider.
"When they first started dating about two months ago they kept it hidden from everyone on the set.
"They didn't want people they worked with talking about it.
"While they have gone out to restaurants and shops together, they prefer to stay home. They watch movies and baseball and spend a lot of quiet evenings alone.
"People close to both of them think they're going to be together for a long, long time."