Amber Heard: No Depo for Me ... I Got a Costume Fitting

Amber Heard is not available to have her deposition taken before her big domestic violence trial next week ... because she has to fly to London for a 3-day costume fitting.

Johnny Depp's lawyer, Laura Wasser, was in court Friday demanding that Amber show up so she can grill her about the alleged May 21st attack. Amber has not made herself available and that's why Wasser went to court.

Amber's lawyer, Samantha Spector, told the judge Amber is now in New Jersey for her best friend's engagement party, and from there she's flying to London for a costume fitting for her movie, 'Justice League.' Spector said Amber won't be back until next Thursday night, hours before Friday's trial.

Sources connected to Johnny are scoffing, claiming the costume fitting is a lame excuse to avoid having to answer hard questions about the alleged attack. The sources say no one ever mentioned the fitting until Friday's court hearing.