Harry Styles fulfilled his long-held ambition of hosting 'The Tonight Show' on Wednesday (19.07.17).

The 23-year-old star had secretly yearned to present the iconic late-night talk show for years and finally realised his dream thanks to the regular host Jimmy Fallon, who presented Harry with a small jade bottle he was given by rocker Stevie Nicks during one of her appearances on the programme.

Explaining the significance of the bottle, Jimmy shared: ''She said, 'Jimmy, open the bottle, blow into it and make a wish, and that wish will come true.' And I did. I won't tell you what the wish was, but, you're here!''

Jimmy, 42, then suggested Harry should make a wish of his own.

Heeding Jimmy's advice, the 'Dunkirk' actor tentatively took the bottle and blew on it, before sealing it up again.

At as that happened, Jimmy clutched his chest and fell to the studio floor pretending he was dead, leaving Harry to walk around his motionless body and assume control of the show.

Looking down the camera lens, Harry then said: ''Hey! We've got a great show for you tonight! Harry Styles is here!''

During his appearance on the show, Harry also discussed his role in the new Christopher Nolan-directed war drama 'Dunkirk'.

Harry plays a soldier in the movie, which centres on the evacuation of troops from the beaches of Dunkirk in France during World War Two, and he suggested the plot might surprise some moivegoers.

The dark-haired hunk explained: ''It's kind of the opposite of what a traditional movie [about] war is. It's not about us being heroes and going and saving the day.

''It's just about community heroism and about how these small acts from civilians and the normal people coming to save us makes this thing. It's very much about the spirit of people and how, when people come together, you can do incredible things.''