Lee Seung-gi is set to return with his signature rock vocals.

On November 3, Big Planet Made Entertainment released a teaser poster for his upcoming digital single By Your Side. The image captures Lee performing alongside a live band, surrounded by drums, electric guitar, and bass.

The single, set for release at 6 p.m. on November 18, is a rock track that blends powerful band instrumentation with Lee's explosive voice. Its lyrics deliver a message of comfort — a promise to always stay by someone's side.

Fans are particularly anticipating his commanding rock tone. Lee has previously showcased his range through acclaimed covers such as "Forbidden Love," "Flight," "Though I Loved You," and "Child of the Beginning," establishing his place in Korea's rock ballad scene.

Celebrating his 20th debut anniversary last year, Lee released the album With, featuring reimagined versions of his hit songs — including "Return," "Because You're My Woman," and "Delete" — in collaboration with fellow artists, highlighting his matured and versatile sound.

Lee Seung-gi is currently serving as the host of JTBC's Sing Again 4.