Tom Cruise, Katie Holmes and daughter Suri reunited with John Travolta and wife Kelly Preston — plus over 4000 other Scientologists — at a massive party in England on Oct. 16, Usmagazine.com has confirmed.

The stars were surprise guests at the 25th anniversary of the International Association of Scientologists held at Saint Hill Manor in East Grinsted, West Sussex. During nearly two hours of speeches, Cruise, 47, briefly addressed the rapturous, fist-pumping crowd: "Because we never took our eyes off the ultimate prize, we stand where we are today," he intoned, witnesses tells Us. "We are in this together!"

When a choir took to the stage, the Cruise-Holmes family stood up with the rest of the audience. "Tom was swaying and looked like he was in heaven," an attendee tells Us. "He was really, really into it. Katie was next to him doing her best to look as enthusiastic. She was clapping along with the

song, but was totally out of sync. Suri was standing by, looking a little bemused in a cute little party dress."

Seated nearby, the Travolta and Preston — still mourning the death of son Jett and dealing with a related extortion trial — were more muted. "John and Kelly were holding hands throughout the performance," an onlooker says. "They look like a very united couple."

Later, during a reception, Cruise was overheard chatting with another American man about the protesters outside the venue. "They're squirrels," Cruise said angrily, according to a witness. "Stuck in an electronic incident. It makes me so angry!"

The family left the party around 11 p.m.; they have a home in nearby Dormans Park.