Our first glimpse of the Medecins Sans Frontieres clinic in Conakry is chilling.
Doctors in yellow and white bio-hazard suits move slowly around a temporary complex of tents and outbuildings like extras in a science fiction film.
Only their eyes are visible behind clear plastic eye guards. Extreme vigilance is needed when dealing with one of the worst most virulent diseases.
And we're here to report on the biggest outbreak of Ebola ever recorded, that's now spread to Guinea's sprawling capital Conakry, a city of two million people.
As you walk into the clinic in the grounds of the main hospital, you can’t get past the security guards without washing your hands and the soles of your shoes in a bleach solution. No-one goes in or out without it.
Inside, there's another level of security altogether: a preparation tent where doctors and nurses gear up to enter the high risk zone.
Carefully they put on Wellington boots, a plastic all-in-one suit, a rubber apron, a plastic hood, plastic goggles and 2 pairs of rubber gloves - no part of the face or body is exposed - because just one drop of bodily fluid from an infected patient could pass on the virus.
This Ebola outbreak in West Africa began here in Guinea in March. It soon spread to neighbouring Sierra Leone and on to Liberia and is now confirmed as the worst outbreak ever.
More than 750 cases have been reported and more than 445 deaths.
The symptoms can be horrific, they begin with fever and diarrhoea - but victims can bleed externally and internally.
When the doctors enter the high-risk zone, they only spend about an hour within it. The plastic suits are too hot for anything more and in the month of Ramadan when many aren’t eating all day long - the risk of overheating themselves is high. One doctor recorded a temperature in the suit of 46 degrees centigrade.
We watch Monia Sayah, a French Nurse with MSF working quickly inside, then, when her time is up, she comes through an exit tent, where she is sprayed with chlorine.
She washes her hands in chlorine in between removing each separate part of her security suit. No risks are taken. Only the goggles and the apron are not incinerated, instead they are plunged into chlorine to kill any trace of the deadly virus. She finally steps out, soaked in bleach and sweat. She tells me how harrowing it can be inside.
The patients with Ebola are totally isolated, so she does what she can to comfort them. She touches them through the plastic to give them some human contact, even though they can’t see her face.
This clinic has seen Ebola victims of all ages. Even a seven-month-old baby. He didn't have the strength to fight the deadly disease.
One of the patients is a woman called Mbalya. She is a traditional healer and caught the virus treating others. She is old and frail, but is fighting it.
We talk for a while across at a distance of two metres, separated by a flimsy plastic fence. The virus is not airborne but it's disconcerting that the doctors in the other side of the fence are fully suited and I am not.
Mbalya then insists on giving a message to others urging anyone with the symptoms to get medical help immediately.
Initially Ebola patients can appear to have Malaria. Victims suffer a fever, headaches and muscle aches. But after a few days the virus can result in haemorrhaging from their eyes, ears and genitals. By then it's often too late to save them.
This is a virus that wastes no time. Symptoms can be sudden and deterioration can be fast. The chances of survival are far greater if help is sought immediately. If not then the chance of dying can be 90%.
But the clinic in Conakry is prepared for that. On one side - are the patients. On the other is the morgue.