This seminar will be held over Zoom. The link will be sent by your local Triangle seminar organiser or you can contact bogdan.stefanski.1@city.ac.uk for link. I will report on some work in progress on type I topological strings on twistor space, and their relationship with integrable but non-supersymmetric field theories in three and four dimensions. This is closely related to recent work of Bittleston and Skinner.