Berlin: The director of a new film conjuring the ghost of a hippopotamus owned by Colombian drug baron Pablo Escobar was shocked to learn how unpredictable and threatening the beasts can be.
Nelson Carlo de los Santos Arias, who made "Pepe", one of the buzziest titles at this week's Berlinale festival, said filming the animals on location in Namibia and Colombia had been dicey for his crew.
"One time we didn't know there were hippos there and then they almost took the boat that we were in and so we almost lost the camera," the Dominican filmmaker told AFP.
"Another time a mother - they are the most aggressive ones - started running and the sound guy almost lost his equipment."
De los Santos Arias noted the animals can run "up to 35 kilometres (22 miles) per hour, these five tonnes of fat".
"You will never think that they are so fast and they're so strong," he said, wide-eyed. "I will not do that again."
All the derring-do however landed the 39-year-old director a coveted slot at the Berlinale with one of 20 films in competition for the Golden Bear top prize.
The docudrama imagines the inner life of Pepe, an African-born hippopotamus that belonged to the cocaine king's private menagerie until the animal escaped and was shot in 2009 on the orders of state authorities.
Through voice-overs, Pepe recounts his terrifying voyage from home across the Atlantic - "a river with only one shore" - and the bewildering experiences that led him to become the first hippo killed in the Americas.
'Realm of fable'
After Escobar himself was gunned down by police in 1993, his ranch and collection of exotic animals, including hippos, were left to nature in an area of lush vegetation where they had no predators.
The hippo numbers exploded and authorities say there are now 160 of the beasts wandering freely around northwestern Colombia.
De los Santos Arias filmed in villages where fishermen feared for their lives - and livelihoods - due to the intruders.
"Their entire life is the Magdalena River," he said. "So imagine this hippo appears in your swimming pool. Because that river is their swimming pool."
The decision to shoot Pepe, as he was nicknamed in the media, proved controversial at the time despite the public safety concerns.
Pepe became a kind of folk hero and a "martyr" while the hippos became part of the "political discourse" in Colombia, the filmmaker said.
De los Santos Arias said he was intrigued by the complex issues the spirit of Pepe raised.
"Because of this action of personification of an animal, we enter in the realm of fable," he said, in a story spanning the legacy of colonialism as well as ecological threats.
"Some will say there is an invasion and that it will destroy the environment," he said.
"But rivers are getting dry in Africa and hippos are dying, whereas in South America, there's a lot of water. And that may be the destiny of a lot of people also, and beings and animals and plants."
Kenyan-Mexican Oscar winner Lupita Nyong'o, jury president at the 74th annual festival, will award the Golden and Silver Bear prizes at a gala ceremony in the German capital on Saturday.