Purpose: To examine the roles of transitional care nurses in an integrated healthcare system and how the integrated healthcare system influences their evolving roles. Background: Transitional care teams have been introduced to enable the seamless transfer of patients from acute-care to the home settings. A qualitative case study of the transitional care team was conducted to understand the changing roles of these nurses in an integrated Regional Health System (RHS) in Singapore. Methods: A hospital transitional team of an integrated RHS was studied. Purposive sampling was used. Non-participant observations and follow-up interviews were conducted with four nurses. Data were triangulated with the interviews of two managers and three healthcare professionals, and the analysis of documents. Within-case thematic analysis was carried out. Results: Three themes were identified: ‘Coming together to meet the needs of all’; ‘Standing strong amidst the stormy waves’; and ‘Searching for the right formula in handling complexity’. These themes have explained on the atypical roles taken on by nurses in their attempts to close the gaps and meet the patients’ needs. Various factors influencing the evolving roles were revealed. Conclusion: The roles of nurses have ‘emerged differently’ from their traditional counterparts. Various nursing roles have been undertaken to facilitate care integration. The findings emphasised the important balance between formal structural practices and informal processes in facilitating and supporting the nurses in their role development.