It's about a man (cop) whose family are involved in a car crash.
He survives, and in one reality, so does his wife. But when he goes to sleep, he wakes up in another reality where his wife dies, but the son survives.
He has different therapists in each reality, and different partners/bosses at work.
Some are born great, some achieve greatness and some have greatness thrust upon them.
The rest of us are a bit crap.