When Stefan accidentaly crashes to a coffin, it falls and the dagger hits someplace and leaves the body. Stefan is freaked, because he can't dagger the original again because that would kill him, so he calls Matt, who is a human and can put the dagger in the place without dying. The reason he calls Matt is he doesn't want to involve Elena, and he also doesn't trust Elena about not telling Damon. But Damon overhears the phone call while Matt is talking (this happens after Klaus gives his ultimatum and leaves), he recognises Stefan's voice, and goes to wherever Stefan is with his vampire speed, without telling Elena where he is going. Matt cannot leave the Grill as his boss doesn't let him, so he calls Jeremy and tells him to go wherever Stefan asked him to go. Tyler joins Jeremy, because he needs someone to talk to after his breakup. They go to where Stefan called Matt to, and bump into Salvatore fight. Jeremy runs and stops them. Then Stefan remembers and rushes Jeremy to inside. He shouts "quick, Jeremy! Stab him!!", because he sees the original starting to wake up. Jeremy stabs him just in the nick of time and he is neutralised again. Meanwhile Damon and Tyler walk in. They start talking about what was that all about. Stefan fills them in. After a brief silence Tyler says "you know Klaus isn't gonna stop until he gets all those coffins back", a brief conversation, and Jeremy finally says "this is too dangerous. If one single thing goes wrong, then none of us are gonna make it out alive!" They all nod, and agree to go with the plan (whatever Katherine's plan is).
On the other hand, I can't think of anything sensible about Elena and who might be chasing her. But one thing for sure, Damon's gonna regret leaving her alone once again.