Ron Howard remembers Robin Williams as a comedy "genius".

Ron Howard

Ron Howard

Howard and the Oscar-winning actor - who committed suicide in August 2014 - starred alongside one another during two 'Happy Days' episodes in which Robin played his iconic character from the hit sitcom 'Mork & Mindy'.

Recalling his experiences of working with Robin, he shared: "He immediately took over, but in the most playful way, you wouldn't believe it.

"Henry Winkler looked at me after this five minute torrent of unbelievable hilarious improvs that sort of included ... like kissing Fonzie on the forehead which I don't think ever made it in the episode, which was kind of just a cartoon come to life."

Ron admitted Henry and himself were both astounded by Robin's talents and ability to improvise.

He told a reddit AMA: "[Henry] looked at me, we just never had never seen a burst of genius quite like that.

"Robin is so missed for that mind, that heart, and that talent. But it was all there on that day, and I'll always be grateful that I got to witness it."

Despite this, Ron said it wasn't all plain sailing, as Robin had arrived two days into rehearsals for that week's filming.

He recalled: "Robin Williams came in very late in the week, now we used to rehearse all week and do this show on Friday right in front of the audience, not live of course, but filmed.

"We started rehearsing on Monday and on Friday we did it. By Wednesday, we still didn't have Mork from Mork & Mindy.

"Everybody was very nervous, they even talked about maybe shutting the show down that week, which would have been very expensive. (sic)"