STORY: Harry, the younger son of King Charles, has brought a lawsuit against Associated Newspapers (ANL), along with John - one of the biggest selling artists of all time - his husband David Furnish, and actors Elizabeth Hurley and Sadie Frost.
The prince, who flew in from his California home, sat just feet away from a large group of reporters, watching intently and occasionally taking notes. His spokesperson said he had wanted to be there to show his support, and that he might attend for much of the four-day preliminary hearing.
Elton John and Furnish arrived during a break for lunch, while Frost was also in court on Monday. None of the claimants are expected to speak during the hearing.
They allege they were victims of "numerous unlawful acts" carried out by ANL titles the Daily Mail and the Mail on Sunday, their lawyers said in extracts of submissions made to the court.