There's a number of things that can cause delays on the London Underground - but a rogue parrot is not usually one of them.
But that's exactly what happened this week and photographer Rob McWilliam managed to capture the odd sight on camera.
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He spotted the animal while travelling towards the Bakerloo line at Waterloo.
He shared the image online and said the animal "caused gridlock" as presumably people were stopping to stare and take pictures.
According to the Metro and the Daily Mail, he wrote: "Last night I was travelling to meet friends for drinks in soho when I encountered this on the conveyor heading towards the Bakerloo line at Waterloo.
"I looked and couldn't see anyone around who looked like an owner; whether it had flown away from them I'm not sure – it caused gridlock on the travellator."
However, another passenger, called Jonathon Carr, said he also spotted the bird, and saw that it did have an owner. He tweeted:
I saw the Parrot of Waterloo. He had an owner pic.twitter.com/43DaZuQDEA— Jonathon Carr (@Jonathon_Carr) March 23, 2016
Back in 2013, a enormous dog was spotted riding on the Tube with its owner, and was so big it actually 'sat down' in its own seat.
And, in January 2015, a full-sized polar bear shocked commuters as it strolled along the platform at Charing Cross station. Oh ok, that one wasn't really real.