Lara croft legend - escaping the knights tomb in England

If you are talking about where you see king Arthur's body, the answer is simple: When you approach bedivire's sarcophagus, the front of it is movable. Press the Y button to grab it, and pull it to the pole on the other side. Once that is done, look for a chandelier in the middle of the roof. Stand in front of King Arthur and grapple it with the grappling hook. Pull it a few times to get it swinging. Then, jump onto the pole. You will see a cylinder dangling from a rope that is connected to the bell. Jump on it and wait for the chandelier to hit the bell. Afterwards, the glass in front of Arthur's body will break, leading you into a cinematic, and the tomb doors will open after Lara takes the fragment of the sword