A life-sized mosasaurus burst through the South Bank riverside path on Monday to promote the Blu-ray and DVD release of the new Jurassic World movie.
Jurassic World's producer Frank Marshall attended the unveiling of the installation: "It's incredible to see the mosasaurus come to life here in London.
"This huge water-leviathan played a crucial part in the film so we're thrilled to be able to unveil it to the British public today.
"It is the biggest creature brought to life on screen in all the Jurassic films and the detail in which it has been created here today is just jaw-dropping."
The sculpture, which has been two months in the making, was created in Cardiff by Wild Creations, who were also behind the velociraptors that appeared at Waterloo Station in June.
Matt Wild said: "We're honoured to unveil the mosasaurus in London today and couldn't be happier with how it's come out.
"The raptors had such an incredible response back in June and when we got the call to go bigger for the Blu-ray and DVD release we were more than happy to rise to the challenge.
"The mosasaurus was first sculpted in three quarters of a tonne of clay then moulded in fibreglass, before being airbrushed to finish.
"We installed it overnight in order to unveil it this morning at sunrise."