Keep following the mission you will eventually meet up with him.

If you mean how do you get into Data Hive, You have to complete Tayari Plaza,Uplift Reserve, Kizingo Boulevard, ONI Alpha Site and NMPD HQ together.

The cast of The Constant Gardener - 2005 includes: Ann Achan as Aduk Lucy Achieng as Member of The Kizingo Arts Troupe Donald Apiyo as Kioko Juliet Aubrey as Gloria Woodrow Suleiman Bakari as Member of The Kizingo Arts Troupe Jeffrey Caine as Club Servant Florence Chamba as Member of The Kizingo Arts Troupe Thomas Chemnitz as Uniformed Policeman Ibrahim Chitaya as Member of The Kizingo Arts Troupe Joe Christopher Rhode as Karl Katherine Damaris as Nurse Ralph Fiennes as Justin Quayle Daniele Harford as Miriam Danny Huston as Sandy Woodrow Nyajima Jial as Esmerelda Abdallah Juma as Member of The Kizingo Arts Troupe Mumbi Kaigwa as Grace Makanga Elzabeth Karanja as Member of The Kizingo Arts Troupe Elizabeth Karanja as Member of The Kizingo Arts Troupe John Keogh as Immigration Official Anneke Kim Sarnau as Birgit Peter King Nzioki as Policeman 1 Andre Leenheer as Shaven Headed Man Jacqueline Maribe as Wanza Kiluhu Richard McCabe as Arthur Hammond Gerard McSorley as Sir Kenneth Curtiss John Moller as Athletic Unshaven Man Juma Musa as Member of The Kizingo Arts Troupe Triza Musimbi as Member of The Kizingo Arts Troupe Eric Mutua as Member of The Kizingo Arts Troupe Anne Mwikali as Member of The Kizingo Arts Troupe Sele Mzamil as Member of The Kizingo Arts Troupe Packson Ngugi as Officer in Morgue Edgar Nicholas Rhode as Karl Bill Nighy as Sir Bernard Pellegrin Steenie Njoroge as 1st Journalist Jane Obada as Member of The Kizingo Arts Troupe Benson Obiva as Member of The Kizingo Arts Troupe Ainea Ojiambo as Police Driver Christopher Okinda as Doctor Leonard Ongaya as Member of The Kizingo Arts Troupe Sidede Onyulo as Jonah Andika James Osoo as Member of The Kizingo Arts Troupe Samuel Otage as Mustafa Bernard Otieno Oduor as Jomo Archie Panjabi as Ghita Pearson Keith Pearson as Porter Coleridge Eva Plackner as Crossing Guard Pete Postlethwaite as Lorbeer Nick Reding as Crick Denis Schnegg as Doctor Rupert Simonian as Guido Hammond Donald Sumpter as Tim Donohue Rachel Weisz as Tessa Quayle Stuart Wheeler as 2nd Journalist Dang Wuor Diew as Sudanese Man

You have to unlock it through achievements.

Buck- Finish Tayari plaza on Normal

Dutch- Finish Uplift Reserve on Normal

Mickey- Finish Kizingo Boulevard on Normal

Romeo- Finish NMPD HQ on Normal

Dare- Finish entire Campaign on Legendary

you have to be in about 11 or up