Michael Caine revealed to HeyUGuys during his 'A night out with... Sir Michael Caine' event at the Royal Albert Hall in London yesterday that Daniel will play his son in Now You See Me 2. The movie is currently scheduled for a 10th June 2016 release. Here's what he said:
“There’s a sequel to Now You See Me and we’re shooting in London. I shoot in December, the whole of December in London, and my son is Harry Potter. I thought it’d be funny, me and Daniel Radcliffe as father and son.”
Update: 4th November 2014: Lionsgate/Summit confirmed that Daniel is joining the cast
Update: 26th November 2014. The subtitle has been revealed: Now You See Me 2: The Second Act.
Here's a short synopsis from Now You See Me (crime/mystery/thriller, 2013) with Jesse Eisenberg, Mark Ruffalo, Isla Fisher and more:
An FBI agent and an Interpol detective track a team of illusionists who pull off bank heists during their performances and reward their audiences with the money. source: heyuguys.com