The Morse spinoff, which has been a regular ratings hit for the broadcaster, features Whately and Fox as Oxford's Inspector Robbie Lewis and DS James Hathaway.
Three new titles for the series have been revealed as 'Generation of Vipers', 'The Age of Foolishness' and 'Death of the Author'.
'Vipers' has been penned by Patrick Harbinson, while Rachel Bennette, Simon Block and Russell Lewis teamed up for the other episodes.
"Lewis and Hathaway have become a formidable partnership not only in terms of cracking murders cases, but also in terms of their popularity with ITV1 viewers, " said ITV's controller of drama commissioning Sally Haynes.
"We're thrilled they are returning to work on some great new stories."
Exec producer Michele Buck said: "Lewis and Hathaway's partnership has grown in popularity with every series as viewers enjoy the fine writing, acting and excellent production values Lewis has to offer."
David O'Neill (Law & Order) has been unveiled as the director of episode one, while Toby Stephens (Die Another Day) is the first guest star confirmed for the latest run.
Morse creator Colin Dexter will continue to act as consultant for the series.