Shia LaBeouf, Josh Duhamel, Tyrese Gibson and John Turturro are set to reprise their starring roles, with Peter Cullen returning as the voice of Optimus Prime. Ehren Kruger, who collaborated in the writing of the second film, was said to be again involved in the writing. Despite having initially been confirmed for the film, and with the film already into principal photography, it was announced that Megan Fox would not be reprising her role from the previous two films. With Fox's character Mikaela being dropped, Sam was assigned a new love interest, who will be played by English model Rosie Huntington-Whiteley. Also, Roberto Orci and Alex Kurtzman, having written the first two films, will not return for the third installment in the series, which Orci had earlier somewhat anticipated, fearing the duo would "risk getting stale". Bay has stated this would be his last installment in the series.