Kiefer trained in Musical Theatre at London College of Music. His credits in training include Alfie, Alfie the musical. Lt. Brown, Six Nights in Naples. Cheshire, Wonderland (original piece) and Moritz, Spring Awakening.
Further theatre credits include; Green Arrow, ExCEL Superheroes! Lorenzo, Twelfth Night (Pell Mell theatre productions) and David, Last Orders (Albert-productions).
Kiefer is also qualified for Sword and Shield, and Knife combat and interns at LSM and Royal Central.