What Happens When A Timing Chain Breaks On A Lincoln Ls V8?

Depends.

At best your car will come to a stop and require a tow to a real mechanic. Replacing a timing belt by the side of the road at night in the rain is not often done.

At worst your car will come to a stop and require a tow to a real mechanic who will then tell you that your engine is totally destroyed and will cost thousands to fix or replace.

This will depend on exactly what engine you have. What car/year/engine do you have?

Just had the secondary chain break on a 2000 LS v8  and lucky me the valves and pistons didn't have sex so it just took a chain.