The Transformers Official Instagram page confirmed that Josh Duhamel will be returning as William Lennox for the fifth installment in the Transformers franchise
An general complaint regarding the Transformers movies is that it gives more focus to the Humans cast than the Transformers, but despite this, most of the people that have seen the movies generally agree that William Lennox is among the best human characters in the movies despite the franchise faults.
No word yet if any other cast members from the original trilogy will return, but Micheal Bay did teased a possible return for Tyrese Gibson in his personal Instagram page, with Duhamel returning it would make sense for Gibson to return.