Hayden Panettiere Reveals Friend's Name Who Allegedly Put Her In Bed With Naked Man

Hayden Panettiere is diving deeper into one seriously dark Hollywood moment from her past -- involving her claim an industry friend basically delivered her to a naked male singer on a yacht when she was just 18 -- and she's naming names!

In her memoir, "This Is Me: A Reckoning," Hayden says the woman -- identified as Stella McAmis -- told her to trust her while leading her downstairs to meet the famous British singer, who was allegedly lounging naked in bed waiting for her.

Hayden says the whole thing was horrifying ... recalling the singer shirtless in bed, propped up on pillows with his arms behind his head, while she could clearly see the outline of his body under the sheets -- all while Stella hyped up his "huge d***."

Still, Hayden admits she climbed under the covers anyway -- not even processing how to say no in the moment because Stella -- who she thought was a close pal -- had told her to trust her while leading her to him.

But internally? Hayden says her heart was pounding so hard, and she disassociated as the shock of the situation hit her. Thankfully, once Stella left the room, Hayden stopped things from going any further -- quickly getting out of bed and arranging to leave the yacht ASAP.

Looking back, Hayden says Stella basically treated her like a call girl ... though she also believes the woman had a chaotic relationship with fame and rich men herself, constantly chasing whoever had the most power and money in the room