Casually interrupt them

Andy makes up his mind. He may not be dating Kate anymore, but he still cared for her, and damned if he was going to let some ass take advantage of her.

Ducking back behind the bend so he was out of sight, he said in a loud voice, "Oh don't worry guys, I'll go find Kate and James and then we can group up!" Waiting a few seconds, he then casually swam around the corner pretending to look around.

"Oh, there you guys are! Come on, we're going to go hang out as a group now!" Andy says cheerily, acting like he just spotted Kate and James

Kate quickly pulls away from James and out of his grasp. "Oh awesome, thanks Andy! We're coming now."

James meanwhile looks decidedly annoyed, shooting Andy a glare that he pretends not to see.

Andy waits as Kate swims past him. As she brushes by him, she looks at him, and silently mouths "Thank you", before continuing to swim towards the others. Andy feels a warm glow spread through him, before shaking it off and following her.