In celebration of its 50th anniversary, SKH Bishop Mok Sau Tseng Secondary School successfully filmed the alumni-composed theme song That Summer on 29, 30, April and 3 May2025. The large-scale production featured performances by 40 choir members and 80 students, with student director Cheng Hei Tung (5D) leading a production team including Chui Hong Ki Kelly (4B), Kwan Ka Lok (5B), Chim Wai Kei Vicky (5D), Ng Wing Yiu (5D)and Lam Chi Kwan (5D), showcasing students' creativity and talent.

The youth-themed That Summer incorporates school history and teacher-student bonds in its lyrics. Filmed at iconic campus locations, the music video blends the choir's melodious vocals with vibrant student performances, conveying deep affection for the alma mater. Throughout production, the student team demonstrated remarkable professionalism in location coordination, shot composition, and logistical support.

The enthusiastic participation made this project not only a centerpiece of anniversary celebrations but also a testament to MST students' unity and innovative spirit. The theme song is scheduled for release in June, accompanied by a commemorative music video as a special gift for alumni across generations.