In conditions matching those of Beijing four years ago, where Armitstead’s team-mate Nicole Cooke took gold as rain poured, Armitstead finished narrowly behind Vos of Holland.
It came down to a straight fight between the two and Russia’s Olga Zabelinskaya, as they shot down The Mall, with a thunderstorm and standing water adding to the danger and Vos edging out Armistead.
Defending champion Cooke struggled to impact on the race after she dropped out of the back of the peloton with two-thirds of the race completed.
With less than five kilometres to go, Armitstead positioned herself on Vos’ wheel, as expectation increased when she entered the final kilometre.
But the Russian, who knew gold was beyond her and was doing all she could to secure a medal, attacked hard, with Armitstead lying in wait for a charge to the line.
In a thrilling sprint finish, Vos pipped Armitstead on the line, leaving her to claim silver, which she declared herself delighted with.
She said: “I’m a bit shocked. I was so glad I committed to that break, but I should have jumped early, but never mind.
“We discussed before what happened in the men’s race that once a group is committed in front, it’s hard to be in the back.
“It’s the most special thing I’ve experienced in my life. It’s crazy and so inspiring.”