Henry's character Henrik Hanssen made his first appearance in Holby last month and has since been causing tension at the hospital as part of his new job as the joint director of surgery.
Speaking in an interview with Inside Soap, Holby's series producer Myar Craig-Brown confirmed that Henrik will soon become the latest character to move over to the Emergency Department for a guest appearance.
Craig-Brown explained: "Guy is actually filming at Casualty at the moment, so the next crossover will air in about three months.
"It makes sense, seeing as we are all in one hospital. In Holby's world, Casualty is just downstairs - even though we film at Elstree and they film in Bristol."
Back in June, it was revealed that the Holby and Casualty teams plan to air "two or three" crossovers each year from now on. Get the Inside Soap magazine on your iPhone or iPad