Riverdale actress Lili Reinhart has blasted an unnamed older actor who tried to take things too far on a nightmare date when she was still a teenager.

The 21-year-old detailed her shocking experience in a lengthy Tumblr post this week (ends13Oct17) in response to the multiple sex assault and harassment allegations made against Hollywood producer Harvey Weinstein, whose decades of bad behavior was recently exposed in articles in The New York Times and The New Yorker.

In her revelation, Lili raged that the man "in a position of power" tried to "take advantage" of her while they worked together on an unspecified project.

"All that matters," the former Surviving Jack star continued, "is that he tried to force himself on me when we were on a date. I had to stop him and say 'No, I don't want that,' and 'I can't do that.' I physically walked away from the situation before it could get any worse. I remember feeling like this was a scene right out of a horror movie.

"I just knew how wrong it felt and that I had been violated."

She finally persuaded the "pretty significantly older" actor not to take her back to his apartment, as he had appeared to be planning: "And I knew if I made it there (his apartment), something bad was going to happen to me," she added.

When she addressed the incident with the man the next day, he told Lili she was to blame "for leading him on", claiming she "seemed like a sexual girl" who would be "down for it".

Lili was terrified to speak out about the drama, fearing "no one would believe her", and admits she worried any complaint she may have made would have led to the production being "halted".

"People would be put out of work," she shared. "I would be looked at as dramatic and a diva, no one would want to work with me again."

She concluded her post by noting that she believes in "standing up for yourself as a woman", stating, "I'm coming forward about my own experience to further express how common these assaults are in this industry (Hollywood) and how important it is that we take action to fight against it."