This was DeNiro’s first comedy, which opened the door for later roles such as in Meet the Fokkers.
The chemistry between Robert DeNiro and Charles Grodin was the main draw. I liked Grodin, but his acting was never great IMO. But, the two worked together so well, I actually watched the whole movie without skipping ahead, which is unusual for me these days.
Midnight Run is actually a great movie, I only watched it for the first time a couple of years ago and thoroughly enjoyed it.