Clearly Keira and Sienna have gotten, uh, extra-close while filming The Best Time of Our Lives with Matthew Rhys. So close that they love to play "games" together even when they're not filming. Games that involve grabbing your colleague from behind while your male co-worker watches.
What? That's not how you and your co-workers kill time in the break room?
[West Wales, UK; May 10. Image via Splash]