Actress Mia Farrow has told Roman Polanski's libel trial she saw him "brush off" the advances of two women in the days after his wife died.
Mia Farrow worked with Polanski for 1968 movie Rosemary's Baby
The director is suing Conde Nast - the publishers of Vanity Fair - over claims he made sexual advances to a woman on the way to his wife's funeral.
Ms Farrow said he was in "really bad shape" after the murder of his pregnant wife, actress Sharon Tate.
The magazine denies libelling him in a 2002 article.
It said Mr Polanski, made advances to a "Swedish beauty" in Elaine's restaurant in New York in 1969 shortly after the death of actress Sharon Tate.
Polanski is testifying from Paris to avoid possible extradition to the US
The magazine now accepts that the incident did not happen when Mr Polanski was on his way back to Hollywood for Ms Tate's funeral but said it occurred about two weeks later.
Ms Tate was murdered by Charles Manson's "family" at the couple's home in Bel Air, California, in August 1969.
Ms Farrow, 60, who became friends with Mr Polanski, 71, after filming Rosemary's Baby in 1968, told the court she met up with him in Elaine's in the days after Ms Tate's death.
Mr Polanski's QC, John Kelsey-Fry, asked her: "During that meeting in Elaine's did you see him behave inappropriately in any way with anybody?"
Sharon Tate was eight and a half months pregnant when she was killed
Ms Farrow replied: "No.
Mr Kelsey-Fry asked if they had been able to discuss anything other than the murders.
She replied: "He was unable to talk about anything else and ...he just kept saying 'Why?' and W'ho would have done this?'... it was the time before we knew who had done this and it was just not conceivable. We couldn't figure it out at all."
She said that the Oscar-winning director "paid no attention [to the women] because we hadn't seen each other since Sharon's murder and that was so huge.
"I think I might have been crying and was hugging him and he just brushed them off."
Graydon Carter, editor of Vanity Fair, was also in court
Ms Farrow added that the director became too upset to eat and so they left the restaurant and "just started walking around and around the block".
"He told me about visiting the house where Sharon had been killed and the others and a little kitten that Sharon had and the kitten was still there in the blood," she said.
Tom Shields QC, for Conde Nast, asked Ms Farrow if she had read about the director having casual sex with other women within a month of his wife's death.
"I feel there's a big distinction - for men maybe - between relationships and having sex," she said.
"If he says he did, I don't doubt it, but it would in no way detract from his feelings for Sharon. I would swear that on a stack of bibles."
Debra Tate, Sharon's sister, attended the hearing
She also spoke of Mr Polanski's "utter sense of loss, of despair and bewilderment and shock and love - a love he had lost".
The actress appeared in London's High Court on the second day of Mr Polanski's libel case.
He won the right to testify from Paris, where he now lives, amid fears that if he entered the UK he would face extradition to the US, where he is still required to face child sex charges.
Ms Tate's younger sister, Debra, who was 16 at the time of the murder, said she spoke to Polanski on the telephone in London after the tragedy.
"He was an absolute wreck, sobbing, weak in voice - I'm sure weak in physical body on the other side of the telephone," she told the court.
She saw him when he came to Los Angeles and he was "heavily sedated to the point where he couldn't walk without assistance".
Earlier in the day, Mr Shields told Mr Polanski he had an "inability to tell the truth when it matters".
Mr Polanski responded by questioning the memory of those who said they witnessed the alleged incident at Elaine's restaurant in New York.
"I am more and more astonished by this phenomenal memory these people have," he said.
The hearing was adjourned until tomorrow when the jury will hear the defence case.
They were told the judge would sum up on Thursday and the case is on target to finish this week.