Korda wanted Donat to make "Hamlet". Instead the actor appeared in Korda's "Knight Without Armour" (1937). Korda became committed to the latter project because of Donat's indecision. Madeleine Carroll had read the James Hilton novel while shooting "The 39 Steps", and had persuaded Donat that it could be a good second film for them to star in together. Donat acquired the rights and passed them on to Korda, although by now Carroll was unavailable. His eventual co-star, Marlene Dietrich, was the source of much attention when she arrived in Britain. Donat was caught up in the furor, and the stress was so great that he suffered a nervous collapse a few days into the shooting; Donat entered a nursing home. The production delay caused by Donat's asthma led to talk of replacing him. Dietrich, whose contract with Korda was for $450,000, threatened to leave the project if that happened, and production was halted for two months, until Donat was able to return to work.