 So Alice has just bought a brand new stretch limo, which is 7 meters long, and she wants to take it out for a nice physics-related joyride. Bob has just the thing. See, Bob has a garage, which is 5 meters long. Now normally Alice wouldn't be able to fit her limo inside the garage, but Bob has an amazing idea. All Alice has to do is just drive towards the garage really really fast at some speed fee. Because as she does so, relativistic effects means the limo will become length-contracted. In Bob's reference frame, the length of the limo will be 7 over gamma, where gamma is of course our Lorentz factor up here. Now if Alice is driving fast enough, she will become length-contracted in Bob's frame to a length shorter than the garage, allowing her to fit inside. Now just as she drives inside, Bob can slam the door shut, and Alice's 7 meter long limo will have fit perfectly inside Bob's 5 meter long garage. Now of course at this point Alice will keep going and smash right out the back of the garage, but that doesn't matter. Alice is wearing her seatbelt, and Bob was planning on rebuilding it anyway. So Alice thinks this is a great idea, she gets into her car, revs up the engine, and goes hard at the garage. But then she notices something. See in Alice's frame of reference, she is stationary, and the garage is moving towards her at a speed V. Now if the garage is moving, this means it's the garage that undergoes length contraction, but it was already too short in the first place. Now there's absolutely no chance of Alice fitting inside, and all she's going to do is just smash through the back of this ridiculously short garage. So how can this be? Who is right? Will Alice fit in the garage? Or not? Now have a careful think about this, because there are some subtleties that make this situation slightly different to the spaceship question.