Prince Harry made a surprise appearance in London on Monday, marking the first time he’s been in the U.K. since his grandmother Queen Elizabeth II’s funeral in September.

The Duke of Sussex, who also hasn’t been home since the release of his tell-all book Spare, was seen arriving at the High Court for the first day of a lawsuit against Associated Newspapers Ltd; publisher of the Daily Mail and Mail on Sunday.

Harry and other celebrities including Elton John and Jude Law’s ex-wife Sadie Frost are suing the company over alleged phone tapping and other invasions of privacy, the Associated Press reported.

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ANL have been accused of “engaging in unlawful acts that included hiring private investigators to bug homes and cars and record private phone conversations,” AP added.

People stated Harry, who stepped back as a senior royal alongside his wife Meghan Markle in March 2020, occasionally took notes and sat two rows behind the leading lawyers during Monday’s court proceedings.

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The hearing is said to last four days and will see a judge rule whether the case should go to trial or not.

People added that Harry had told his father King Charles and brother Prince William that he’d be in the U.K., but reportedly won’t be seeing them.

Charles’ trip to France was postponed amid mass protests in Paris and Bordeaux, but he will still be heading to Germany on Wednesday.

William, on the other hand, is currently on vacation with his family for the Easter break, Hello! claimed.