Busy Philipps claims James Franco physically assaulted her on the set of 'Freaks and Geeks'.

The 39-year-old actress - who has previously discussed the incident but has now provided more detail - has accused the Hollywood star of being overly-aggressive towards her during their time on the comedy series.

In her new book, 'This Will Only Hurt a Little', Busy explains: ''It felt like over the summer he had read 'Easy Riders', 'Raging Bull' or something and had decided that the only way to be taken seriously was to be a f***ing p***k.''

Busy recalled one particular day on set, accusing James of stealing her lines.

The actress explained that tension gradually increased between the pair.

She said: ''It's not like I had that many on the show. I wanted my f***ing line.''

Later, they shot a scene in which James and Seth Rogen - who played Ken Miller - were asked to run after a vehicle that'd been pelting them with water balloons.

Recalling her own role in the scene, Busy said: ''The director asked me to sort of hit James in the chest as we ran after the car and say my line.''

She added: ''James did not say his line in response. Instead, he grabbed both my arms and screamed in my face, 'DON'T EVER TOUCH ME AGAIN!' And he threw me on the ground.''

The incident left Busy in a state of shock, though she tried to contain her emotion.

She said: ''Immediately, I could feel the wet hot stinging of tears, but I tried like hell to suck them back in.''

The actress ran to Linda Cardellini's trailer after re-shooting the scene and ''dramatically sobbed'', but she claims that her co-star barely got a ''slap on the wrist''.

Despite this, Busy says James offered an apology to her the next day.

She said: ''He smiled and hugged me. And I don't need to tell you this, but James is a f***ing movie star. He was horrible to me, yes, but he's also gorgeous and charming as hell. That's where the manipulation lives.''