You've likely seen the videos on social media: exhausted doctors and nurses pleading with the public to stay inside, to limit the spread of COVID-19 and avoid overwhelming hospitals.

But what is it really like inside hospitals in Canada right now? One of them, Humber River Hospital in Toronto, opened its doors to allow CBC News rare access to observe a day in the life of the hospital, in the midst of a global pandemic.

Tonight on CBC's The National, Adrienne Arsenault takes you inside the ER and ICU to meet the sick and those trying to save them. 'Inside the Fight Against COVID-19' airs Monday at 9 p.m. ET on CBC News Network, 10 p.m. on CBC Television.

The scene at the Toronto hospital was unlike the chaotic scenes reported in some hospitals in countries like the U.S. and Italy. Still, beneath the surface, there was fear.

"It's not calm, when we're going in to do these procedures even ourselves who are trained, our hearts are racing," says emergency room physician Dr. Tasleem Nimjee, of working with COVID-19 patients.

"What we don't want is to have it so that you're doing case after case after case, that's when everybody is at highest risk. That's when you're more likely to contaminate yourself."

Here's Nimjee, explaining the fears and challenges of working amidst the pandemic:

Dr. Tasleem Nimjee talks about testing, PPE, and the risks of working with patients with COVID-19 3:41

Nimjee knows that as time passes, people might forget why they're isolating at home. "When you've been at home for a long time self isolating and not going to work and not doing the things that you normally do… you don't have any sightline to what it's like in the hospital and what's actually going on," she says.

Before long, one suspected COVID-19 patient was admitted to the hospital with a fever and shortness of breath. Here's how it happened: