2001 Mercedes Benz 320sl Engine. Cranks. But. Won't. Start

Ok the first thing to check (and I don't mean to insult you) is to see if it had gas.

With that done next, check the fuses (especially the ignition fuses and the fuel pump fuse).

It they are all good. Remove the air cleaner, at the throttle body, enough to spray carb/throttle cleaner into the engine (about a 3 second blast should be enough). Put the air cleaner back into place and try to start the car.
If it now starts or tries to start, suspect a fuel system problem (such as a bad fuel pump, clogged fuel filter). If that's the case more diagnostics will be necessary. Let me know how these tests turn out and I'll try to guide you further if needed.