Ashton Kutcher and Mila Kunis are reportedly living together.
The two former That '70s Show co-stars are yet to confirm they are a couple but are said to be inseparable and cohabiting.
A source told The Sun newspaper: "They're basically living together. Like any new couple in love, they're pretty much joined at the hip.
"They've been sneaking around for months but there's only so long you can keep it quiet."
The insider added: "They're staying with each other most nights. Mila's practically moved in to Ashton's Hollywood home."
His marriage with Demi Moore broke down last November, following reports of Ashton's cheating.
Demi has since ended up in hospital after having an apparent seizure while smoking an unknown substance.
Mila and Ashton were caught kissing at the wrap party for his latest film, a biopic of the late Apple boss, Steve Jobs, at the weekend.
The actress recently admitted that she doesn't find herself particularly sexy.
Mila said: "I appreciate the attention, but I don't think of myself as particularly attractive.
"I do have a pretty sharp sense of humour, though, and I think that has helped me."