More details about the multiple historical sex offence allegations against Cardinal George Pell have emerged as witnesses give evidence at a hearing to determine if he stands trial.

Pell has been charged with multiple historical sex offences involving multiple complainants, and is fighting the allegations at a month-long committal hearing before Melbourne Magistrates Court.

The 76-year-old is due to return to court on Tuesday for the third day of evidence in open court.

The pre-trial hearing began on March 5 but was closed to the public for several days as the complainants gave evidence, as required by law in sex offence cases.

The hearing opened to the public and the media on Wednesday.

On Monday, the court was told Pell is accused of abusing a complainant while watching the film Close Encounters of the Third Kind at a country Victorian cinema.

Pell is also accused of committing a sex offence at a swimming pool, and abusing another complainant during a water-skiing outing at a lake.

As many as 50 people, including the complainants, will be called as witnesses during the hearing.

Magistrate Belinda Wallington will then decide if there is enough evidence for the case to go to trial in the Victorian County Court.

Pell was charged on summons in June 2017 while he was in Rome.

He took leave from his position as Vatican treasurer to return to Australia to fight the charges.

EARLIER: Cardinal George Pell is accused of abusing a complainant during a screening of the film Close Encounters of the Third Kind at a country Victorian cinema.

Pell, 76, returned to Melbourne Magistrates Court on Monday for week three of a committal hearing as he fights charges of multiple historical sex offences involving multiple complainants.

The court has not released details of the charges.

Defence barrister Robert Richter QC questioned cinema sales manager John Bourke whether he or his staff were alerted to someone being abused during a screening of Close Encounters of the Third Kind.

"The situation is this: if someone is heard to scream out in the balcony, an usher would have heard?" Mr Richter asked.

"If someone was heard to scream or yell ... that would have been something that would be reported or investigated?"

"If a person yelled out, that would be investigated," Mr Bourke said.

The hearing, which will determine if Pell stands trial, continues before magistrate Belinda Wallington.

Australian Associated Press